I'm not sure about the 256MB x1800 xt but I can tell you that even though I lean towards nVidia I am really glad I got in on the Compusa X1800 XT 512MB card for $299 AR. This card has the most stunning graphics I have ever seen. I first noticed it when I loaded up Doom 3 - wow! I know that game, and I've played it with many cards (x800 xl, 6800 ultra, 7800gt, x850 pro). With the X1800 I get a depth of color and detail that I have never seen. Half Life Coast, with HDR full, and everything pumped is also a joy to experience.
I'm not trying to start yet another nVidia/ATI war (we've seen enough of those, right?), and, like I said, I tend to gravitate to nVidia over the long run, but, man! This x1800 has sweet, sweet graphics like I have never seen before in any card.
This is a great time for gamers if you got the wallet for it!!!