6850 all the way. Got a Pair of XFX's for a friend of mine, solid cards. If you have a high high res then 6870 is best.
Great cards, though the fan profile on the XFX is a little aggressive, so perhaps the Gigabyte one would work.
ST
what do you mean they are aggresive?
never heard that before referring to fan placement, no idea what it means.
Also, i love xfx lol, i ordered 2 6850s today, can't wait for them to arrive.
edit: speak of the devil, jsut checked, they are in shipping now, maybe i'll get em today