In no particular order:
I've got Sennheiser HD25's. They're awesome kit: light, clear and really comfortable. I use them for DJ'ing and can keep them on all night without any fatigue. the only thing I might change in the future is the pads and go for some velvet ones. I've seen some pretty cool customised ones too, for that bit of individuality.
If you like them no problem... But imo (and 90% of other people) the D2000 and Momentums are better than the D600 so that is a bit misleading.