Pros: Highly detailed, neutral, goes well with whatever you throw at it
Cons: Can be sibilant (requires 100+ hours of burn in), springy cable, unhelpful strain reliefs.
These are amazing IEMs for the price. It is a balanced IEM and isnt lacking across the spectrum. They can handle pretty much every genre you put through these.
The bass on these is excellent, it rumbles down deep, while being very quick and tight. But the main thing which I love about the bass on these is the 'weight'. When the track calls for it these really do move a whole lot of air and slam it against your ear drums.
As for the midrage, I would say it is neutral, but on some tracks the mids are somewhat warm. With that said.. I'm not sure if the mids are actually warm, or the IEM is just neutral and reproducing warm mids...
The vocals on these are amazing as well. It is very intimate and sweet. These really do make vocals come alive and are also (very) forward (T.V. Carpio's cover of I Want to Hold Your Hand from the Across the Universe OST).
For the treble, I'd just like to say that it doesn't contain enough sparkle to satisfy any treblehead. Despite that, these still contain enough sparkle and detail to satisfy my needs.
Instrument separation on these are also great. I can just 'lock onto' an instrument and it seems like it's the only one playing. A funny remark made by a friend of mine (who is just your typical consumer) told me that he didn't like them because all the instruments playing is all "separated" and not "playing together". (I think he likes to have zero separation and to have a tiny soundstage)
The only con I can think of is the sibilance. Every lyric that has an 's', (and 'd' and 'th') on some recordings are unbearable. A good example of this would be the song Heartquake! by Sienna Skies.
The only remedy for this is to burn them in for 100 hours. After you hit that mark there may still be some sibilance but they will eventually be non-existant (I have put through around 450 hours through mine).
I am VERY happy with my GR07s!
Here's a list of some of the songs I used to test out my GR07s (all songs are lossless or high quality lossy MP3/AAC):
Perfect Future - Make Fun
Perfect Future - Colonization
Sienna Skies - Heartquake!
T.V. Carpio - I Want to Hold Your Hand [Across the Universe OST]
Joe Anderson & Salma Hayek - Happiness is a Warm Gun [Across the Universe OST]
Papa Roach - Getting Away With Murder
Versailles - Silent Knight
Uppermost - Born Limitless
Uppermost - Satellite
Morgan Page - The Longest Road (Deadmau5 Vocal Remix)
with some classical here and there.