1200w microwaves are typically very large, with at least 1.5 cu. ft. of interior space. When compared to other microwaves, these high-wattage microwaves typically cook foods faster and do a better job at the defrosting tasks. Surprisingly, 1200w microwaves rate around average for power. The majority of 1200w units are countertop, though there are some built-in models available as well. Panasonic is the leading brand for 1200w microwave models.