XFX were pretty poor at the start, nasty customer service, poorly built cards (over heating, artifacts) they even sold 6800's with slower memory than others (i remember the 6800GT they sold came with 900Mhz memory)
since then i think they've moved up, i think they are now one of the number 1 nvidia board partners, always seem to get a good supply from nvidia. ive just moved from a leadtek 6800gt to xfx 7800gt's and well, i think the XFX cards are better built IMO. i changed the HSF on the 6800gt for a Zalman VF700, and i was shocked at how baddly the stock HSF was applied.
these XFX 7800's are very well built, single slot copper coolers, a healthy overclock, and solid contstruction....they have a aluminium bar running down the side of the card for support.....very very sturdy. and to top it off....they run 20 degrees cooler with stock cooling than my 6800gt did with its stock cooling. oh....and theyre wisper quiet, even during games
so for me XFX>Leadtek. im having a good experience.
ill back VIAN though, BFG got it down.....the support is supreme.