Microwaves & lasers aren't comparable. The power used to 'lase' the gas in higher end lasers is RF (similar to microwave). Microwaves heat from the inside out by making the molecules move quickly. Lasers on the other hand 'oblate' the surface w/coherent energy. The heat is just a by product of the friction caused by the impact. Lasers are neat.
All I know for 100% certain, is AVE from YouTube's microwaving a bearing w/a wet towel wrapped around it works like a charm.
Oh, and Lasers 'ablate' not 'oblate', my bad.