I owned the NFB10SE and it was a very good match for the LCD-2 in balanced mode. I moved on from it because the upper mids were dry and grating with the HD650. I didn't own the HD800 at the time, but I suspect it would be a very bad pairing. The HD800 deserves better and you may end up hating its presentation if your ancillary gear isn't up to scratch.
I agree with olor1n. If your hardward is not up to snuff. You might not like the HD800s at all.