Hi Rookie and welcome,
If your room isn't huge (5000 to 8000 cu. ft.), then most well-designed AV receivers will have ample power (100 to 120 watts per channel) to drive the 4-ohm M80 towers (part of the Epic 80-600 system) to very loud clean levels.
However, don't pick the Yamaha as some models in the past overheat or shut down driving the 4-ohm load of the M80s. The brands of AV receivers that have no problems driving the M80s are: Denon, Sherwood Newcastle (Axiom sells Sherwoods on our site), Rotel, NAD, and Outlaw Audio.
One subwoofer isn't a factor in terms of driving a system, as all subwoofers have their own internal power amplifiers. The AV receiver just supplies a small 2-volt signal to the subwoofer and you can add additional subwoofers later on if you wish, driven by the same AV receiver.
Regards,
