I'm not sure about the new ar9380's they have almost identical architecture to the 9280 but with an extra stream. I have a 9280 and it is amazing. Atheros chips have excellent compatibility.
so good that i installed them in all 3 of my computers. Every possible feature backtrack offers works great on them.
For GPU acceleration i would recommend Nvidia, as i believe even slower nvidia cards work much better than ATI cards and are more compatible. Otherwise the more streaming processors the better.