I'm late to the party but I'll add my 2 cents worth. Well actually I'll keep the 2 cents 'cause I need every penny I can get so I can get M80s as soon as possible.
Thats a fine spouse you have there. Regardless of how you decide, give her a big hug for all of us and tell her just how great she is.
I had the good fortune to be able to listen to both in and a/b audition recently. There is a definate difference between the 60s and 80s. At $300 more its a simple decision.
They do both sound very good.
Blame it on those nasty people at Axiom for pricing their top line speaker at pocket change above the M60.
Edit: Can't comment on the Onkyo as I don't know anything about it.
