Went for a local HD800 preview yesterday, I can summarize by saying they were good. But at their price, I wasn't expecting anything less.
The setup was a T+A CDP, with a Lehmann Black Cube Linear.
Very nice soundstage, not overdoing it like the K701. Imaging was precise, and resolution was very good. Clean, extended, smooth and transparent. Though all of my friends who went to the preview agreed that it definitely needed a better amp. The Black Cube was clearly struggling with the HD800, I had to turn it to 2 o' clock on the dial. Bass was accurate, but lacked the extension and definition that I felt was due to the amp. Slightly lacked in dynamics, which I also feel was due to the amp.
Oh yes, it definitely looks good (read: expensive) and it's VERY comfortable. Light, huge earcups, padding was just right. Cable was nice and solid too, you don't get any tangly mass like some other headphones.
The listening session was only about 25min, so please take this with a pinch of salt.