ctown,
Alan's definitely not lying! The Axiom's will surprise you with how good they sound over speakers like Klipsch.
Although of course Alan is the expert, I have to second his opinion on the M60's, especially since you are using the Pioneer amp (it would have a hard time driving the M80's to good levels). M22's would be "thin" sounding in a room that size. I used to own M22's, and although they were some of the best speakers I have ever heard at that size and price, they just didn't fit my room, and I needed the $$$ to upgrade to M80's, so I sold them and my M3's. I still miss them...
But I digress. M60's, to me, are definitely your best choice, matched with an EP500 sub.
