Even the Denon receivers in the $300-400 range have been driving M80's with no problem for many years. My 2805 from years ago, and my current 3805ci drive my m80's to levels most don't listen at, and don't break a sweat.

Keep in mind the m80's are well above 4 ohms for most of the frequency range.

M80s VP180 4xM22ow 4xM3ic EP600 2xEP350
AnthemAVM60 Outlaw7700 EmoA500 Epson5040UB FluanceRT85