I must admit that at first I was a little disappointed when I upgraded my GPU from GF4 Ti4200 128MB but then I finally got the courage to over clock my new Leadtek GF5900 128MB to Ultra rate and it really toke off!
Original 3D setting is 400/850 and the Ultra is 450/850. Not a big difference but it makes a huge difference in the game. I run at 1600x1200x32 and get 40-80 fps of line. No compression and anisotropic. I tried it in perfect landscape but excellent looks better and perfect cuts the fps in half.
So let the ATI etc rants begin. I don't care what you use as long as you are happy with the result! I'm happy!! I'm in LOVE!