I was really happy with LCD-2 but HD800 are just a lot better for my needs... I guess I love huge soundstage with precise imaging and instrument separation the most (and the neutrality and great balanced bass etc. etc.). From high-end headphones I've had, Denon D7000 really didn't do it for me and therefore I knew that FUN headphones are not for me. Then, LCD-2 with very good balance but in the end, they were too stereo-ish with too much dominant bass and little bit more shelved in treble than ideal.
HD800 do not have a single flaw to my ears... It's just a completely perfect headphone. I really tried hard to find anything not good enough but this headphone is just... huge. If I ever wanted to switch, the successor must share nearly the same sound characteristics and cost less, or be significantly better (and not cost 2x more).