You should not have any issues. People have been driving the m80's for many years with various Denon models going back as long as I can remember, including my old 2805. Keep in mind, the majority of the frequency range of the 180 is above 4ohms.

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