You can basically ignore the wattage ratings for speakers. The more important spec.s are sensitivity (e.g. how efficient are they), freq. response +- 3dB and impedance.

You'll be more than fine with 50-100 watts of power from the amp with the speakers you are considering. Axioms are very efficient so don't require a lot of power to drive them and all but the M80's run at 8 ohms which is easy for amplifiers/receivers to power.

Paul