iXBT Labs posted a comparison review between ASUS RADEON HD 4850/4870 and GeForce GTX 285/295
>> ASUS RADEON HD 4850/4870 and GeForce GTX 285/295
GTX 295 is a very fast card, the first of its kind so far. But much depends on its price tag. Perhaps, it's cheaper to buy two GTX 280 cards that will apparently be faster in the SLI mode? So be sure to watch the prices.
>> ASUS RADEON HD 4850/4870 and GeForce GTX 285/295