I'll have to agree that the Stax 009s sound better than the TH900s, but I'm still not wholly convinced on the HD800s. I'm currently waiting for a set to show up in the B&S section and might give it a shot. My experience thus far is that the HD800s really lack bass, which is a little disappointing when listening to some of classical pieces like the 1812. Haven't tried the LCD-3s but have heard good things about them - how do they compare with the TH900s?
One issue with the TH-900s vs the HD800s is that the TH-900s sound fantastic out of pretty much anything. Heck I loved them out of my (now sold) HeadAmp Pico portable amp. But the HD800s are a very difficult beast to tame. It wasn't until I heard them on a B22 or a WA2 that I really heard what they were about. Then I moved up to the WA22, Liquid Fire and now my GS-X and the HD800s scaled further to higher levels.