$200, ouch.
Where are you from? Around here (USA) it's maybe $100 difference. $450-$500 6800U and $550-$600 X800XTpe. And I seriously consider X800XT as another alternative in the $450 range.
Only you know if money is no object, but $200 seems awfully high for what you get. If i were going to spend a big premium, I'd make sure it's on a HIS X800XT IceQ II VIVO Limited Edition, and not just any old XTpe.
<A HREF="http://www.hardavenue.com/reviews/hisx8001.shtml" target="_new">http://www.hardavenue.com/reviews/hisx8001.shtml</A>
<A HREF="http://www.guru3d.com/article/content/141/1/" target="_new">http://www.guru3d.com/article/content/141/1/</A>
But I guess it just depends as to how much you are willing to spend to have the absolute best. Above the $350 or so for a 6800GT, it costs alot to increase performance. Personally, I just can't imagine actually spending more than $450 or so for a 6800U or plain X800XT, even if I could. But that FX53 just seems to be begging for a X800XTpe.
<A HREF="http://service.futuremark.com/compare?2k3=3400555" target="_new"> My</A>
<A HREF="http://service.futuremark.com/compare?2k1=8268935" target="_new">Gamer</A>