Yes the M80s do fall in the range of high a efficient 4 ohm load with their 95db rating. They are also an easy 4 ohm speaker not dipping below their 4 ohm rating.

What I would do is get the M80s, if that is what you want, try them out with the Yamaha and see if it has any trouble pushing them. If you make sure to have enough breathing room around the receiver my bet is it will do a good job for your needs.

Rick


"A fear of weapons is a sign of retarded sexual and emotional maturity." Sigmund Freud