Pros: Fun sound, no bass bleed, outstanding build, incredibly low price, comfortable
Cons: Not crisp enough highs for some, adjustable headband can expand accidentally
Accessories: Includes a pouch and cable. Pouch is well-built, compact, and stylish. Soft, flexible cable has never tangled for me in my time with it. Right angled jack is durable and well-relieved. Remote is a little plasticky, but works well.
Build Quality/Design: Absolutely fantastic at the price point. Mostly plastic build is sturdy enough for portable use and not brittle at all, though I wouldn't recommend transporting these in a bag outside of their case for extra assurance. Adjustable steel headband is solid, though the ratcheting mechanism can feel a little loose on my unit. I have not seen this problem in any other reviews, so I don't think it's a major issue. When shaken, they don't rattle at all. The high-gloss black finish is discrete but sleek, and the angled design on the earcups is a nice break from the flat or rounded back designs we so often see. The blue accents in the pivoting joints and on the cable provide nice contrast without being flashy at all.
Comfort/Isolation/Leakage: Because these are on-ears and I had mostly worn in-ears to this point, it took me a while to get used to the different form factor. However, after warming up to that, they are very comfortable. The earpads are soft but firm enough that your outer ear cannot feel any part of the earcup itself. They do rest on your ears, so if these are your first pair of on-ears make sure to stretch out the headband over a few nights. This can be done for this pair by putting them over their box. Clamping force is there but not as strong as something like the Beats Mixr. Padding on the headband could be a little thicker, but what's there is enough to be comfortable. Isolation is good but not the best due to the form factor. The more expensive UE 6000 has better passive isolation due to its over-ear design. Leakage is minimal at normal listening volumes.
Sound Quality: I'll be splitting this into four parts: bass, mids, treble, and soundstage.
Bass - Sub-bass has good impact, but could be more present. It is definitely not invisible and adds a good body to the sound. Bass drum hits are prominent when necessary but never overshadow the sound. Daft Punk's "Lose Yourself to Dance" has a correctly thunderous bass line, while the synth kick drum hits at the beginning of U2's "Beautiful Day" are well-restrained and appropriately subtle in comparison to the bass guitar line. Slight mid-bass boost adds warmth but not bloat. Natural-sounding bass overall with both real and synth sounds. Not the tightest bass ever, but not boomy either. Emphasized, yes, but not Beats. Overall, fantastic and somewhat atypical bass for the price point in that it is well-controlled and has accurate dynamics.
Mids - Very rich due to the slight mid-bass boost. Vocals, both male and female, are well-portrayed and full. Katy Perry sounds fantastic on the chorus of "Roar," with her unique timbre accurately portrayed. Jon Foreman's varied timbres on various songs by Switchfoot are accurate as well, with his growls and falsetto contrasting quite well. Pharrell's falsetto on "Lose Yourself to Dance" is appropriately airy but not entirely so because of the added body. Instruments are portrayed as backing up the vocalists and never overshadow. Acoustic guitars are warm but not very sparkly, emphasizing body resonance over string. The Edge's chimey electric guitar on U2's album The Joshua Tree are airy and bright, while songs like "Vertigo" have a nice girth to the overdriven guitars. Harder bands like Skillet sound quite forward and aggressive compared to softer fare. Pianos have a good top end and a pleasing tone, if occasionally warmer. Overall, very accurate mids in relation to the other frequency ranges, but warmer than neutral, which I greatly prefer.
Treble - This is where the flaws come in. Highs are recessed to avoid any sibilance, giving the headphones a relaxed sound. The roll-off stops at around 10kHz, giving those extremely high frequencies a very slight boost to enhance clarity. This works really well, as all the other frequency ranges sound a little crisper than they would without that slight boost. I prefer relaxed highs to sibilant highs; however, these are not as crisp as even I would prefer sometimes. I do have an iTunes equalizer preset that is slightly V-shaped for these headphones, boosting 1k on up to add a little extra air. They do respond to equalization well, never sounding artificial. Overall, the highs are rolled-off, but because there is no sibilance I don't fault them too much.
Soundstage - Adequate width and height, surprisingly deep. Portrays intimacy well, as Bastille's "Pompeii" pushes the lead vocals in front of everything without ever being in-the-head while the drums and bass are well-placed behind the vocals. The treble roll-off makes them lack slightly in air, so as previously mentioned I do boost them. However, because the roll-off is mainly focused on reducing sibilance, most instruments and vocals don't sound dark, being very adaptable to what the recording calls for. Overall, solid soundstage for price, but higher-end products sound larger.
Conclusion: I can't recommend these enough for everyone that is looking for on-ears on a budget. Their build and comfort is solid and works well on-the-go, while the sound is fun but not overly aggressive. They are not audiophile grade, but would satisfy those that want slightly stronger bass, warm and full mids, or non-fatiguing highs. These are my favorite pair of headphones, and their current price point makes them an absolute steal. Get them while you can, as they have been discontinued by Logitech.