Hello Matt,
NoRap has essentially nailed the differences between Kkipsch speakers and Axioms.
For years, Klipsch has generally used horn loading on its tweeters and sometimes midranges, which helps achieve very high Sound Pressure Levels (SPL) with very few watts of input power. However, the horn loading produces aggressive strident highs that are musically unnatural and inaccurate. Horn loaded speakers are the norm for movie theaters, rock concerts and large venues to achieve high-volume sound over a very large area without having to use tens of thousands of watts of input power. But you don't listen to those speakers for musical accuracy. Certainly dialog intelligibility is important for home theater (and in movie theaters). Of the Axioms you picked up, I'd upgrade the center channel, the VP150, which at best is barely adequate. The VP160 or VP180 are vast improvements over the VP150. (Your Klipsch center channel may be fine as an alternative if it doesn't make strings, brasses and music vocals too aggressive and sibilant.) I'd go with the rest of the Axioms you picked up except for the VP150, and sell the Klipsch models. The Axiom M80s are capable of very clean high-volume levels in domestic living rooms, even very large ones. And they are no inherently strident or edgy, unless the source material has been EQ'd to sound that way, a so-called "presence peak".
Axiom's M80s and M22s, and others in the Axiom lineup, are musically neutral and natural, with excellent spaciousness in the soundfield, and they produce really excellent frequency response congruity measured objectively.
Going back several decades when I was Editor-in-Chief of Sound Canada (later Sound & Vision Canada), we objectively tested a Klipsch Heresy loudspeaker at the National Research Council anechoic chamber in Ottawa, followed by double-blind listening tests. The resulting frequency response curves were among the worst we'd ever measured, and in listening tests, the Heresy was found to be extremely coloured, unnatural and musically inaccurate. I have not heard recent models of Klipsch speakers but I suspect the design recipe hasn't changed much.
Bridgman's comment of "a different sound" for Klipsch is very polite and understated.
Regards,
Alan
