Its pretty simple. If you go AMD, Sapphire. If you go NVidia, EVGA. I have had Sapphire since my 9700 Pro and not had one card fail me yet (9700 Pro, 9800XT, X850XTPE, HD2900 Pro, HD4870, HD5870) and now have a HD7970 Dual X and Vapor X and HD7870 Dual X.
Sapphire is the AMD brand to go with.