I agree with John. In this post, Axiom's President, Ian Colquhoun, describes the two speakers this way: “The M60 is an 8 ohm version of the M80. You will not lose any sound quality, imaging, or dynamics. The difference is in the clean achievable output levels, but keep in mind that going for high clean output should be done by purchasing both the M80s and big power; either one in isolation will not achieve the goal.” Comparing this to your receiver choice and description of your listening preferences, the M60s appear to be a much better match. It seems that the $300 price differential between the M60s and M80s -- which according to PriceGrabber is 90% of the cost of the receiver -- could be spent better elsewhere or simply saved.

I'm not familiar with the receiver, but your speaker choices are excellent. You should be happy with either the M80s or M60s as your mains, but I would save the money and go with the M60s.