From what I remember from Tube Amps. They should have no problem with driving the M3 speakers. The amp says 3.5w but that is before being over driven. That is what gives the tube it's unique sound. The actual amount of wattage required by the M3 is not really that much.

Anthem: AVM60
Axiom: ADA1000, LFR1100, VP180, QS8, EP500, M3, M3comp
AudioSource: Amp One/A