Well, looks like you & me Toy!!! The M60s should do fine. However, sounds like you have the space for the M80s to work, assuming you will be sitting 12' or so back from them. You are sure to have a reciever to handle drive 4 ohms. You can't make a mistake with either choice. If the $$ don't matter and the Axiom folks didn't try to get you into the M60s for some reason, go for the M80s. Bigger will yield more soundstage and depth.
The other consideration - if you go with the M60s, you would save $300. Also, more money frees up with the M60s because you would not need to get a receiver that can drive 4 ohms. The savings lets you get more stuff from your shopping list earlier.
I believe you have already made up your mind to grab the M80s based on your exuberance
. The important things here, within your budget, are to 1) get whatever makes you happy and 2) make sure you get the items that completely avoid the ".... what if I had just spent a little more" or "I wonder how those M80s would have sounded?". In a democracy, everyone should spend 'til they are happy!
