Pros: Clear mids, not too bright, controlled bass, great isolation, good soundstage
Cons: Earbuds are not really comfortable.
The GR02 is certainly an amazing IEM for 40 dollars. It took me a while to get used with it, but it is great sounding. Soundstaging is pretty good, as I tried with a few live jazz and classical recordings. The bass is very controlled. Initially, the bass might be a little soft, but after messing around with the equalizer, I got the best bass I could get from the GR02. The bass might go over the other parts at times, but it depends on your music and how they were mastered.
I daresay the GR02 is actually a great all rounder IEM. It sounds good out of the box. Hook it up to your player and you'll be amazed.