Darksable, my card was perfectly operational, and had great performance. I just didn't find crashing to be of my expertise in gaming. My case is high-end as the rest of my specifications. As of the problems of this card, It could be good for some people, depending on your preference, what you're using the card for. Don't forget, the manufacturer of the card is Sapphire. Sapphire is of the lowest brand name GPU's, and don't always work as well. Same as ZOTAC. Oh, and the 7870 XT does compete with the 660ti actually, the benchmarks display that some games run better on 660 ti, and some 7870 XT.
I, here probly have the best experience of graphic cards, because I upgraded to the 660 ti from the 7870 XT, and the 660 Ti has much better performance. (In my case). Oh and Physx actually supports 22 games , mind you.
Note: I am not attempting to be negative about the card xD, I am only telling you of it's capabilities and how it Is, but then again, up to you.
Oh, and from the 7870 XT to the 660 Ti, my card has run perfectly. It's amazing.