Pros - Highly neutral, balanced and articulate. Bass is all there, not exaggerated.
Cons - Does require quite some hours to get rid of the sibilance mentioned by others. Not rugged.
With the strong dollar the GR07 "Classic" is currently $83. It would be my nomination for the greatest value in IEMs, period. One of the best in audio of all categories. I had another pair for years and while not exactly fragile, I did a couple of minor repairs to keep them going for 5 years of gym use twice a week. Some users will want to use tips other than included- I like the Sony.
I have the Bass Edition. They're good earphones. I found the sound quality a little lacking in detail in the upper mid/treble range. I'm not sure what that was about, since I eq'd them to near flat response - they just never sounded right with rock and heavy metal. My Shure e2c's are much more detailed. They did have nice extension all way from sub bass into the ~10khz range with a little help from the eq on the top end. Overall, they do sound good (when sealed). I like them better than the Sennheiser Momentums (in-ear) and the RHA MA750 as far as sound goes; the GR07 is more neutral and detailed than either then Senn's or the RHAs. I'm not sure why these are marketed as the "Bass Edition;" the bass is pretty neutral/flat.
I was never able to get a good fit/seal. I even tried the meeaudio m6 triple flanges, but they went just a tad too deep into my ear canal and the included bi-flanges wouldn't remain sealed. Something about the square housing and the nozzle prevented me from ever getting a comfortable fit. Maybe it's just my ears; clearly others are having better luck. OTOH, this is the first IEM that I found uncomfortable. I do like the included earhooks and found a similar product on amazon for use with my other earphones.
I do have to ding these pretty good in the value department. You can get two pairs of the NVX EX10S for $70 or $65 for a single pair from sonicelectronix.com, and those are very close in performance to the GR07. The NVX are probably made by vsonic for NVX or in the same plant that makes the gr07; I know NVX has used other companies to make their equipment on the car audio side. That means you're paying anywhere from 2x to 4x the cost for the vsonic for a similar product. The RHA MA750, which is in the same price range (but different sound signature), has far superior build quality. The ~$100-$150 category is really competitive with some balanced armature IEMs getting into that price range, the Shure se215 has a detachable cable, many competitors offer a mic/remote in that price range, etc, etc, etc.
The overall sound is similar to the Audeze LCD-2F - slightly on the warm side of neutral, but without the ultimate resolution the LCD-2F has. And easier to drive so you can plug them into your phone. The bass is all there but it's not bloated or enhanced like it is with so many IEMs. The treble is all there but at natural levels so they don't sound bright. The mids are just slightly recessed but still sound natural with classical and acoustic music. And the entire frequency range is integrated smoothly with no apparent peaks or troughs. That's quite a lot considering the price is around $100. Can't find much if anything at twice the price that has sound as good as this. They don't have reference level of detail, but enough for serious listening, yet still enjoyable and not fatiguing for long listening sessions.
I went through several different IEMs before I finally found these. Etymotics had crystal clear mids but no "air" with a rolled off top end. The other IEMs had muddy bloated bass. The GR07 classics were just right.
I can listen to these all day - and sometimes do.