I might as well chime in here, since it's late at night and I've come to really appreciate my GR07 Bass Editions.
I bought mine off of a seller here after recently losing my beloved GR06s, and I basically cried for the two weeks I didn't have them. I broke down and bought them.
They came in new condition with around 150 hours of burni-n. I'm interested as to how they sound at 0 hours, because when I first tried them I could immediately notice a focus on bass. It seemed as if the low end was overpowering the mid, with recessed vocals. I used to have the bass on my rockboxed clip zip at I believe +3 bass, and I turned that down to +0.
I burned them in for a couple hours, and two days later I'm listening to some Dash Berlin/EDM/Trance at 5am in the morning. Don't know if it's the mental burn-in, getting used to the bass, or whatever but I'm really starting to like these.
I remember with the GR06, when I first tried them on, I could hear a LOT of sibilance. I'm pretty sure that mostly went away after burning in and 6 months of ownership. These GR07 BE have zero sibilance!
Wish I had my GR06 to compare with though, REST IN PEACE I HOPE WHOEVER FINDS YOU TAKES GOOD CARE OF YOU ):
Also wish I could compare these to the GR07 MKII, but I'm poor now.