I'm a former Aperion owner who switched to Axiom.
The Aperions are very good for what they are, but they do not come close to the Axioms for overall sound quality in my opinion. The Aperions are definitely a little more laid back, and as others have pointed out they would be good if you're going for 5-7 identical speakers.
If, however, you're going for a true home theater, I think the Axioms are far superior. It will cost more to get one of Axiom's better center channels & QS surrounds, but the slight boxiness of the Aperions bugged me for movie dialogs. To me the cost increase was modest, and the improved sound was absolutely worth it.
My testing proved to me that even in 2 channel stereo the Axioms also won out by a large margin.
Rich (M22, VP150, QS8, M2i, SVS 20-39PCi)
