I think the best regionals are SkyWest, Horizon and Air Wisconsin. AWAC is good if you are East Coast, SkyWest if you are West. Horizon is the Alaska feeder and is great if you live NW.
But, Horizon has a longer time to captain upgrade, and is a lot smaller. I also think they are not short of pilots...can anyone confirm this? From what I have heard, AWAC and SkyWest are both short of pilots, but not extremely so like most of the other regionals. I believe SkyWest is bigger than AWAC. SkyWest also has turboprops, as does Horizon, while AWAC is all jets.