I would never own another ATI card.
Maybe they are better now, but in the past I've had horrible experiences with their drivers and support. Also they never seemed to be quite 100% compatible with a lot of things... lots of graphical glitches, etc...
Of course this was a few years ago, but I still have that "taste in my mouth".
I don't understand how performance can get any better, at least for my gaming needs. 90% of the time at MAX settings (1280X1024, 1024 texts, hi-res, all sliders max) I'm pegged at my refresh rate (75fps). Of the other 10% I'm at least 60+ most of the time. The absolute LOWEST I've seen even online is 40FPS, and that was about 20 planes flying around a base on fire while zoomed in. If it wasn't for the framerate counter, I wouldn't have even noticed.
FSX, the only other high graphical demand game I play, even at MAX SETTINGS on everything, I still average 18-20FPS... From what I understand (from reading their forums and other research) this is about the best you're going to expect, unless you have a quad core processor, and two 8800GT's using SLI.
Now.. onto working on my free-track project...