I'm trying to decide between crossfireX 6850's and SLI GTX460's.

The 6850's seem slightly faster than the 460s and use less power.

Is there any reason I should choose the 460s over the 6850s?

also does anyone have any good/bad experience with Visiontek?

They seem to be the only AMD/ATI brand with a lifetime warranty outside of XFX and I do not like XFX. Any suggestions on what brand?