Pros: Really excellent sound... IF you use the right source and eq! Pretty good with classical and acoustic music, but really shines with my dark electro!
Cons: Harsh, weak imaging, deceitful, some users may find sibilant, some users may find blissful. Deafening.
I used to use the ck10 and ex700 to complement eachother as my standard IEM's, which was a nice pair of two very different IEM's, I used the ck10 much more, but I liked the sound quality of the ex700 sometimes, if you click on my username you can find my ck10 review where I compare them with certain songs and sometimes find music quite a bit more enjoyable with the ex700, factoring in price and the qualities I liked in both, I leaned more towards the EX700, and I ended up selling the ck10 to explore other IEM's and kept the EX700, and I do not regret this. The most vivid difference you ask? the EX700 could convey emotional expression via music where the ck10 could not, it is like natural and enveloping versus synthetic and accurate.
In regards to the oft-mentioned sibilance, I must be technical and digress, I don't think the EX700 is sibilant, at least not like the CK10 or the SA-5000 which is what I call sibilant, especially the SA-5000 where "s" sounds are actually resonating into your nasal cavity, but I could handle that, it was kinda cool.
The vice of the EX700 is it's just harsh in a dissonance of the mids kind of way, which becomes literally deafening with extended use, it's literally impossible to listen to the EX700 with sony hybrids, flat eq, and high volume, impossible, after half an hour my ears are ringing, after an entire 7 hour plane-trip, it'll take my ears a day or two to completely normalize again, like I was at a harsh concert! I have however learnt to circumvent this flaw, so I now use decored Shure Olives tips, along with eq'ing, my source of choice is the Teclast T51, and now I just get the best qualities out of the EX700 without much harshness left, the best qualities are IMHO excellent transparency, tonality, decay, resonance and sweetness/clarity, the latter of which I attribute to the 6kHz FR boost, but I do find the imaging in these really quite weak especially on the Y axis, and I certainly miss the flat-FR of the ck10. If I could sum up the EX700 in a few words I would call it the "harmony of dissonance" IEM, or "the deceitful angel", whatever Sony has magically done to the housing or driver of the EX600/800ST/1000 it seems to have recorrected itself into the "harmony of resonance" IEM instead.
It seems like the EX600 is the new recommendation now, but if you can pick up an EX700 for less than the EX600, or would like something with a different flavour than the EX600 and can handle some minor eq'ing or tip experimentation, or perhaps would like more of a collectors item product, I insist it is worth it at that price, for the sound signature.
The EX700 doesn't have a good reputation on head-fi, but I find this is slightly erroneous, I think newcomers and veterans alike should be able to appreciate it's high level of sound quality, one such example is when my ex girlfriend was trying some of my different IEM's, and to her "they all sounded like earphones", until she heard the EX700, that one stood out to her and after listening to some pop and dub-step from her laptop she said "I feel like listening to all my music all over again!", and I have seen reviews on the internet in the same vein.
There has been some discussion on the FR graphs of the EX700/600/800/1000 created by sonove.angry.jp, mostly along the lines of "what was Sony thinking?" with the 6kHz boost, but it is now clear to me that this boost is intentional, as we can also find it in high-end custom IEM's like the Rooth LS8 which even goes over and beyond whatever Sony was thinking with that SS.
Source synergy is important too, I do most of my listening with the Teclast T51 which has a good synergy with the EX700, another strength it has, source transparency, I can now hear the difference between my laptop and T51 clear as day, which was much harder with the ck10 as it is more forgiving and just takes whatever signal it gets and says "let's ck10 this", whereas the EX700 is let's the signal shine through, albeit it is stained glass.
On the T51, the eq allows for adjustment in the 60Hz, 300Hz, 1kHz, 3kHz and 6kHz range, looks pretty useless right? No, not with the EX700, as 1kHz and 6kHz are important sectors of where you have to eq it imho.
I usually adjust the eq like this:
So as you can see, 4dB less at 1kHz, that is quite a decrement, but that is what it takes, and then 6kHz +2? not necessary, but it sounds good! boosting the natural peak exactly where it is, improving sweetness and detail just a tiny bit more along with the reduction of harshness at 1kHz, the HO and LO both sound good on the Teclast T51 with the EX700, but the LO is the vivid, clear, clean and sweet one and thus my favorite here, however I use the HO quite a lot so I can adjust the volume and it sounds fine with pop and stuff.
In Foobar2000, I can't adjust 6kHz, I can only adjust 5kHz and 7kHz, that adjustment doesn't sound very good, 5khz sounds OK, but not 7khz, which starts learning towards piercing, so I leave them alone.
In Foobar2000, I can't adjust 1kHz either, only 440 Hz, 622 Hz, 880Hz and 1.2kHz, you have to play around with those to get a good sound. The eq adjustment and sound-quality out of the Teclast T51 is on a whole different level here though.
So what of genre? I said I thought the ck10 excelled in trance music, smooth detail and excellent imaging, so I listened to more of that and similiar electronic music, but it performed at a pretty high level across the spectrum.
With the EX700 I find I'm listening to more alternative rock, like live björk recordings, and quite a lot dark electro, harsh EBM, where the bass impact, clarity, tonality and transferral of emotion suit that music very well. Of course I'm listening to a few old Nirvana albums now too, where the rawness, decay, transparency, texture, shimmer and spirit gives any music like that a good character, likewise these are well suited for piano's and female vocals, combine that with bass-impact and you have a winning IEM for pop and r&b here as well.
The weakness again is violins, it sounds pretty good, but I'm very picky there and haven't quite found the IEM for my classical music tastes yet. Yet another weakness is imaging and layering, I miss the flat-FR and addictive pacing and speed of the ck10, they can't quite keep up there, but these are very different IEM's. Some recordings will also lose some crunch or character with the eq adjustment, and have the harshness without it, so I find sometimes there isn't a perfect solution and there will always be some hassle with these deceitful IEM's, which is a shame.
I'd have to expand this into a proper review with music links to go into detail in this section though, I might do that when I'm home again (travelling right now, writing on my laptop with wireless internet) and have proper amplification and sources to be more just, as I only have my laptop soundcard and Teclast T51 here right now, this review is not final and I may finalize it at a later point and reserve the right to some slight adjustments. ;)