Although ATI cards may have better AA, in most cases, the performance gap between the cards is too big for the ATI to beat, thats comparing a 4850 and a 260 GTX...but when youcan compared 4870 and 260 GTX then thats a different story. I mean there are exceptions where in grid the 4870 1 gig pretty much matches the more expensive 280 gtx, but I mean what about 90% of the time.
I really don't think the 4850 beats the 260 GTX lol Sorry but thats hard to believe for me
Don't forget the 260 GTX has a higher bus width and more vram. Lets not forget overall more power.
Yes you do have some nice rigs.
Though I would choose the 4870 1 gig ICEQ. very well priced card...seen it for 220$ in stores in Toronto. Not sure how prices are on ur end.