Admittedly, I took far too long to post this review. I wanted to try a different approach that involved becoming accustomed to the signature followed by a period without them, and then a reintroduction. It's been about six weeks since I received the unit. I've done week long periods with and without them. 
The reason for this decision was two fold:
1. It's the first dual dynamic IEM that I've given significant head time. 
2. There were/are some awkward inconsistencies with the sound signature that I was/am hearing. It was my hope at the time to be able to narrow the the reasons behind them. More on this later.
 
After realizing that I had too many notes and they were harder for me to characterize than originally anticipated, I decided to write this review while listening to them after a short break and give my overall thoughts from this session. My previous notes will still be a factor in what I write, but hopefully this gives more clarity to my thoughts. 
 
Again, I'd like to thank Brainwavz for the opportunity to review these. As others did, I received a review pair to keep similar to the S5. It's a nice gesture of confidence in the Head-Fi community.
In similar fashion, I'll avoid adding pictures and statistics that a quick Google search can provide.
All the usual qualifiers apply: IMO, YMMV, OMGWTFBBQ, ROFLCOPTER. This is just my experience. Yours might be different. 
 
For those that don't like to wade through the paragraphs of information that most reviews provide, here is a succinct synopsis: 
 
 

Initial Impressions: 

From my notes 6 weeks ago, I thought they sounded clear with a nice sense of balance. I found the bass to be soft and lacking texture. The mid range was enticing, forward, a little dry, but enjoyable. 
 

Methodology: 

I gave them 5 hours of listening the first day to become accustomed to the signature. They were then burned in for quite some time using set of burn-in tracks with mixed tracks, pink noise, and 5 minute breaks every hour on repeat. 
They were burned in for over 300 hours in total throughout the process. I initially began my process after ~150 hours as per my usual.  I continued to listen to other headphones/earphones.
Then, as mentioned above, I took week long breaks. I also spent full weeks only listening to the R3. My reasons for this will be further discussed in the following sections. 
 
Listening was done casually at home and while out shopping. Detailed listening was done in a quiet office. A/B testing done as well with different gear and Fiio HS2 used occasionally for quick switching of sources or headphones.
 
I avoided reading any other reviews before writing this one to avoid bias. 
 
Chains used:
1. PC USB/Optical>>>Audio GD NFB-15>>>R3
2. Fiio X3>>>(Topping NX1/C&C BH)>>>R3
3. Rockboxed Sansa Clip+>>>(Topping NX1/C&C BH)>>>R3
4. HTC One M8>>>R3
 
Tips used: Supplied tips, JVC spiral tips, Sony hybrids, Sennheiser double flange. 
 
Test tracks: Many albums in my collection were listened to in full with a number of mixed in individual tracks, but here are a few specific tracks used.
                     Track formats included 256-320kbps mp3, FLAC, WAV files and a few youtube videos for variety.
 
 

Build Quality & Acessories:

Oh Jetpack. It's awkward. The cable is a heavy, bouncy, rubbery monstrosity. Plenty of nice accessories included, solid 10/10 in my mind. The bulky shell may or may not affect your fit depending on ear shape. 

Comfort/Fit:

Average comfort. The rubbery cable was very noticeable over the ear and raises up at times until pulled tighter with a shirt clip. Long-term comfort has been poor. After about an hour, I found that the area where the cable meets the body rubbed my ear the wrong way. Tips didn't seem to have too significant of an effect for comfort, though I did favor some more than others. In particular, I liked the stock clear tips that weren't quite as firm. I found that they tend to start slipping from my ears. I'm not sure if it's a result of the cable or something else. I tried to wear larger tips to offset the pull, but found that I couldn't handle the loss of comfort. Occasionally, I' would double check their positioning to make sure they are still in place. This was more of an issue when out and about than in the office.  

Isolation/Leak: 

Average to below average. Noisy locations will be noticeable. I found their isolation to be slightly less effective compared to the S5. Leak wasn't an issue. 
 

Bass: 

The moment I listened to the opening kick drum and first few bass string plucks in  Jessica Lee Mayfield's - "Our Hearts Are Wrong", I knew that the bass and I were going to be at odds. That particular song is very bass heavy. The R3 does bring the quantity of bass in many tracks to manageable levels. This was one aspect that I appreciated for a number of bass heavy tracks; However, it was also the bane of bass light tracks. 
As mentioned in the Cons, I found the bass to be two-faced or fractured. I tried my best to determine its cause, but wasn't able to pin it down in a way that I could explain in a clear fashion. In short, it seems certain frequencies are emphasized. It felt like there were peaks and valleys in the bass than had a very noticeable effect on impact and levels. It didn't seem like a clear line that is normally present where people can say, "Oh yeah, it has a mid bass hump and rolls off in the sub-bass which explains...blahblahblah." - Not the case here. Some songs had the low impact that they normally show, while it was next to non-existent in my other test tracks. I wish I could articulate it better. That said, there is a significant roll off in the sub-bass at about the 50 Hz mark. Below 30 is pretty much a black hole. 
In this moment, as I listen to a number of tracks I find the duality. Some show nice, low impact. Others that should have the same feel like the kick drum or bass is hidden behind a glass panel or being hit by a pillow rather than a mallet. 
One final beef was with the lack of texture. I found it really was missing that detail that comes with a more articulate bass. The overall tone felt smoothed over and pillowy. 
 
 

Mids: 

A nice forward presentation in the mids. It balances well still with the rest of the spectrum. A much desired addition following the soulless mids of the S5. As mentioned in the brief summary above, I find them slightly dry with a touch of warmth. It's a neutralish presentation of the mid range that in some ways reminds me of a less refined HE-560. One of my favorite signatures centers around the mids, so this was a nice change of pace from my generally bass oriented collection that includes the JVC FX-850, among others. 
 

Treble: 

Queen's song "Killer Queen" will pretty much violate my ears if a headphone/earphone is even a little hot, sibilant, etc. These do a pretty good job. Overall non-fatiguing but will undoubtedly be too lack-back for the treble lovers. Smooth, but still with a decent energy, particularly in the lower treble region. Not a whole lot of the sparkle. Hints of sibilance on already sibilant tracks, but that's normal. 
 

Separation/Clarity/Detail:

I would say that it is a notch above average in this category. Decent separation and clarity. A bit thicker sounding than the S5 that suffered from a thin/recessed mid range that killed baby seals. Enough detail to satisfy. Without a doubt some loss of detail and clarity in the bass with roll off and fluffy presentation that lacks in texture and articulation. 
 

Soundstage/Imaging:

The soundstage felt slightly more intimate than I've been used to but not in a cramped way. The positioning feels a intimate. This can be good and maybe a little bad for some live recordings. I'll explain way as it has to do with the way that I perceived the soundstage. The best way I can think to describe the shape is an taking a basketball and half way deflating just one hemisphere. The width sound above average, the behind depth the same. The forward depth, or the space in front of me seems as though its distance has been cut in half when compared to behind. 
 

Source/Amping/Tips: 

The R3 did seem to scale a bit. More important, for me,  was the added power that seems to add a bit more life to the overall sound. :

• Audio-GD NFB-15 
• Fiio X3 + Topping NX1 (Low gain, high was noisy and gave no play with the volume)
• Fiio X3 + C&C BH (Line 2, switches off, gain 'High'). 
• Rockboxed Sansa Clip+ (Forgot to experiment with attaching amps) 

 
I didn't find a lot of difference when tip rolling. Insertion depth didn't change the sound enough so I ended up liking the stock, clear tips. They are comfortable and didn't negatively affect the sound. I thought a narrow bore might help the bass, but the effect was minor and inconsistent so I reverted. 
 

Final Thoughts:

I want to say that I enjoy this earphone. It's far from perfect, but it has qualities that are becoming harder to find in a V-shaped market. The mid-centric presentation is a welcome addition to my collection. The bass can be a bit of a letdown on some tracks, but it can also be a boon in taming overly bass heavy tracks into submission. It can help you see your much listened to tracks in a new light. It suffers from some inevitable design issues, but overall a durable and enjoyable earphone. As I look at the $115 asking price on Amazon right now I asked myself the question, "Is it worth that price tag?" To some, yes. I think it would fit nicely into the $99 category, but what's $15 anyway?

First I'd like to thank Brainwavz for the opportunity to review these. As others did, I received a review pair to keep. It was a very generous gesture. 
Plenty of people have already posted all the pictures and statistics you'll ever need, so this review won't contain them. 
All the usual qualifiers apply: IMO, YMMV, OMGWTFBBQ, ROFLCOPTER. This is just my experience. Yours might be different. 
 
For those that don't like to wade through the paragraphs of information that most reviews provide, here is a succinct synopsis: 
 
 

Initial Impressions: 

The first day I listed for ~6 hours. I listened for an hour at a time with an hour break in between. 
Out of the box I thought the bass was bloated, the Mids recessed and lifeless, and the highs peaky and fatiguing. I was pretty disappointed and not particularly looking forward to spending more time with them.
By the end of my last hour of listening I my hears were fatiguing and I was happy to have them out and get them on the burn-in station.
 

Methodology: 

As mentioned above, I gave them 5 hours of listening the first day to become accustomed to the signature. They were then burned in for the next week using set of burn-in tracks with mixed tracks, pink noise, and 5 minute breaks every hour on repeat. 
They were burned in for ~150 hours before listening again. During that week I listened to all of my other cans. 
 
Listening was done casually at home and while out shopping. Detailed listening was done in a quiet office. A/B testing done as well with different gear and Fiio HS2 used occasionally for quick switching of sources or headphones.
 
I was pointed to the S5 thread, but instead decided to avoid reading any reviews before posting my own. I figured it would keep me from adding any additional bias. 
 
Chains used:
1. PC USB/Optical>>>Audio GD NFB-15>>>S5
2. Fiio X3>>>(Topping NX1/C&C BH)>>>S5
3. Rockboxed Sansa Clip+>>>(Topping NX1/C&C BH)>>>S5
4. HTC One M8>>>S5
 
Tips used: Supplied tips, JVC spiral tips, Sony hybrids, Sennheiser double flange. 
 
Test tracks: Many albums in my collection were listened to in full with a number of mixed in individual tracks, but here are a few specific tracks used.
                     Track formats included 256-320kbps mp3, FLAC, WAV files and a few youtube videos for variety.
 

1. Jessica Lee Mayfield - Nervous Lonely Night : The first minute of this song can tell me a lot about a can. This will seem odd, but the pencil tapping at the start tells me a ton about timbre and a bit about depth. The generally forward vocals of the entire "Tell me" album help point out recessed mids quickly. The bass comes in strong with lots of quantity and impact to let me judge the low end presence and texture. I could go on. It's just a track that works for me. 
2. Queen - Killer Queen  :  One of my sibilance test tracks, though it's much more than that. It's another track that can really let you individually identify a spectrum of specific quality attributes or flaws.
3. Paramore - Hallelujah  : The recording/mastering, whatever, sounds just terrible on the deluxe mp3 version that I have. I use it to test how forgiving a can is. 
4. Pantera - Cowboys from Hell; Cemetery Gates; Floods : It's Pantera. No more explanation needed. 
5. Lisa Hannigan - Live from the Troubadour in W.Hollywood. :  This is a special recording that I have from a live concert I attended.  I'm frighteningly familiar with the venue/performance and how it should sound. I use this to judge soundstage, imaging, timbre and separation. 
6. Rage Against The Machine - People of the Sun :  Bass. 
7. Metallica - (Anesthesia) Pulling Teeth / One/ etc - Lots of reasons
8. Lana Del Rey - Lolita/National Anthem/Carmen : Lots of reasons but in general for her vocals that can sound like thick, warm syrup. 
9. Geographer - Kites :  I like this for cohesion. Some cans make it sound disjointed or all jumbled up. 
10. Filipe Melo · Ana Cláudia // Spiegel im spiegel (Arvo Pärt) : It's beautiful. Noise test. Timbre. Naturalness. 
11. Girl Talk - Let it Out  : It's fun. 
12. Dr. Chesky - The Ultimate Headphone Demonstration Disc - Soundstage, imaging, dynamics, etc. 
13. Many, more. 

 

Build Quality & Acessories:

I'll keep this short.
The build quality is solid from tip to earphones. The flat, rubbery cable might not be your cup of tea. It can be bouncy at times when walking and add some mechanical noise. That's what the over the ear wear style and a shirt clip are for. Ample accessories and travel case. I really cannot think of anything else they should have included except perhaps a pair of wide bore tips for comparison, but they were probably after a specific tuning. 
I wasn't sure where to put this particular piece of information, so I'll go with right here - I notice a bit of driver flex in both channels. Nothing crazy like cheap IEMs, but there nonetheless.

Comfort/Fit:

Average comfort. It doesn't seem to molest my concha/external auditory meatus regions at all. Tips determine the comfort more than anything. Additionally, the cable mostly goes unnoticed over the ear but has a habit of twisting. It's best when it lies flat up and over the ear. If it twists, you'll notice.  
 

Isolation/Leak: 

Average again. Nothing special to report. They are right in the middle. Noisy locations will be noticeable. No specific issues with leak but can slightly vary depending on tips/seal.
 

Bass: 

Burn-in did seem to help the overpowering, bloated bass from my first impressions a little bit. There is solid impact. It still is noticeably loose and has a "one note" kind of texture. 
It has a mid-bass emphasis but does have pretty good extension though it's overshadowed at times. The bleed into the lower-mids is very mild and isn't much of an issue. 
When using wide bore or triple flange tips that help to tame the bass quantity, I preferred a high gain setting on the amps to keep the impact and help bring out a little texture. 
Overall, one of my least favorite types of bass.
 

Mids: 

I think people might disagree with my opinion of this part the most. I find the mids to be dry. My first though about the mids is what lead to "Succubus" part of the review title - They sound like the life had been sucked from them. Tracks that usually are bring a lot of emotion, even goose bumps and send shivers up my spine 100% of the time were reduced to zombie-like shells. Clearly I'm exaggerating with my description, but it's noticeable enough to bother me. This isn't something that might go unnoticed depending on one's headphone collection and preferences. 
The mids are slightly recessed. They are a small step back from the rest. Very non-fatiguing overall, smooth. The exception would be in the far reaches of the upper mids/lower treble.
 

Treble: 

Sparkly. These can bring some nice shine. I don't find them particularly extended, however. There are some peaks and dips that can cause an odd tonality depending on the tip/source/track. The upper mids/lower treble. If I had to guess, I would say peaks in the 1-2k and 7k regions. I found these peaks to be unbearable before burn-in. It was the part that caused me the most fatigue. Afterwards, I don't seem to have any issue. One could argue that I've adjusted to the sound, but I hadn't listened to them for a full week and had been using my usual cans. Take that as you will. 
 

Separation/Clarity/Detail:

This is where I find that these can shine. I particularly enjoy the separation. Good detail and clarity. This pertains specifically to using wide bore or triple flange tips. As mentioned in "The Skinny", fast metal guitar solos go under the microscope with these. Each note is distinguishable. The stock and Sony hybrid narrow tips tend to congest the sound a bit. They still maintain good separation, but it really takes off with other tips. It's a trade off. YMMV and I suggest plenty of rolling until you find a sound that suits you best.
 

Soundstage/Imaging:

I find the soundstage to have good width but lack depth. Sounds like everything is standing in a straight line from one side to the other. Imaging doesn't seem to suffer too much from the lack of depth. I'm still feel that positioning is good. The slightly recessed Mids might give the illusion of depth. The issue becomes very apparent using binaural test tracks as well as live recordings.
 
 

Source/Amping/Tips: 

The S5 didn't scale particularly well though I did find myself having a preference when it came to the dac/dap.
In order from favorite to least favorite:

• Audio-GD NFB-15 
• Rockboxed Sansa Clip+ (no amp) 
• Fiio X3 + C&C BH (Line 2, switches off, gain 'High').
• Fiio X3 + Topping NX1 (Low gain, high was noisy and gave no play with the volume)

 
I didn't try the clip+ much with an amp. I found that I enjoyed it solo and the one time I tried with an amp connected it wasn't big enough for me to keep testing. 
The S5 low end responds to high gain with added impact and a bit more texture. It really didn't need an amp otherwise as it can easily be driven from a cellphone to blistering volumes.
 
Tips seemed to have the largest affect on the sound. Wide boar vs narrow bore are extremely different. The rest of the tips were pretty much the same except for the triple flange. Internal auditory canals can vary greatly from person to person. So your experience with these tips might also vary from my own. I'll reiterate my previous recommendation to spend some time tip rolling. 
 

Final Thoughts:

The Brainwavz S5 offers a trade off of benefits and flaws. It doesn't match up well with my personal preferences. I could see myself using these as a benchmark for separation with the right tips. In fact, it almost felt like the music's tempo slowed and allowed me a matrix style glimpse and otherwise extremely fast sequences. The sparkle is a friendly and welcome addition to the sound, even with the occasional peaky regions. Unfortunately, the dryish mids, loose bass and lack of depth make me reconsider their place in my line up. 
I feel like there is a lot of competition in the $40-100 earphone catagory. I feel like the S5 might have a difficult time standing out among the crowd. 
 
In the future I'd like to see a tuning that tightens up the bass and reduces the upper-mid treble peak. I think that would help bring the overall timbre, especially the mids.