With the search you'll find a lot of stuff about a lot of different speakers from each company. I'll try to give you some specifics. I have a Polk (RTi8s, CSi5, FXi3s, Velodyne CHT12) home theater and have Axiom M22s for stereo in another room. I am very happy with both systems. You can't go wrong with either system you are considering, but I'd probably go with the Axioms. You'll probably like the M22s and QS4s better than the Polk options. The CSi series is outstanding but I wouldn't go Polk just for that since you'll probably like 4/5 Axiom speakers better. It seems as though you are limited to bookshelfs up front and I agree with you that the M22 seems to be better set up to push more air and I consider that a big factor.
As for subwoofers, I love my Velodyne, but I have seen reviews suggesting that the Hsu and SVS offerings in the same (<$500) price range are better.
I hope this helps.
