I've run a Denon 3312ci, Pioneer SC-67, and an older low end Pioneer Elite model with the following speaker configurations in parallel. Currently it's the Pioneer SC-67.

Left Channel: 2 M22's 8 ohm each.
Right Channel: 2 M22's 8 ohm each.
Center Channel: 1 M22 at 8 ohm, 1 VP160 at 8 ohm.

Never had a problem. I'm not sure if an M80 would draw more or less current/wattage/whatever than my current configuration.

https://docs.google.com/spreadsheet/ccc?...amp;usp=sharing