Hi, back again;)
From your earlier thread; Your current CPU will limit it, but the performance at 16x10 will be so high as to maker the limit of no real consequence.
I`m sure others will say the HD4850 might be a better choice and, right now, it would, but you are planning on keeping this rig for some time, so, for you, I think the 260 is probably the best long term (in PC time anyway)way to go.
With the prices so close, and your long term aims in mind, I`d put the EVGA first because of its long warranty, and the XFX with its shorter, but still long, warranty a very close second with the OC card last.
I was giving the hd4850 some serious thought - I think the main thing which put me off is the heat it pumps out, and the fact it doesnt vent it externally. My bedroom is a real suntrap and the case gets hot atm with the 7900gtx, and that has a slot cooler which vents the air out as it is. Having a hot card which vents internally, plus hot room = a bit of a worry.
I know some versions have a slot cooler, but these all seem to be nearing the £150-60 mark, and for that, the jump to the 260 seems logical for 40 quid.