i can say that I've noticed quite a difference. Photoshop/Macromedia studio load way quicker in X64, and I have noticed that while many games don't get "higher" FPS, i have noticed that they don't dip as much during action sequences. RTS games seem to have less graphical lag when moving large armies. I've had problems with mounting tools (the only ones i have found only support ISO), but daemon should be releasing v4 which they have stated will have 64 bit compatibility. It's also built on Server 2003 x64 code, so it is a bit more stable. Overall i don't know that i would have paid the full price for it (I got it for free with my 32-bit copy at my school). before you buy, make sure all your hardware has x64 drivers though