I juggled and I juggled between a GTX 480 and a HD5870. Finally decided to plunge deep and grab an Asus GTX 480.
Sure it runs a lot hotter than GTX 260 but surprisingly, it's not that much more noisier. Guess I need to fiddle around fan speeds to make it slightly cooler but a bit noisier. I really don't know which would be the best tradeoff.