I was looking at one of those too, but then I found an ATi x800GTO for 5$ cheaper, that was better.
The X800 has twice the pipelines that the 6800XT has. I believe it has better clocks too.
EDIT: The clocks are just about the same
The 6800XT has 350/1000
The X800 has 400/980
But the extra pipelines are worth it.
Here's the link:
The spec's say it only has 12 pipelines, but it actually has 16 as Sapphire has unlocked them for everyone.
Good luck on your decision.