You forget nvidia's drivers. The last two screwed up the fan and burned up many cards.
Also, catalyst 10.3 is supposedly pretty good, probably cuz of all the money ati is raking in right now, givingthem more money for development.
What I mean, yourface, is I'm pretty sure none of the 200 series can do the new dx11 features like tessellation because they don't have the proper hardware parts in the card for it.