We all camp and live differently, but if I was doing my build over again, I would not order the microwave. I'd rather have that space for more galley storage. I find that even with two 6v batteries and solar, the micro can take the polish off the battery charge. Micros use a lot of power but for a relative short period of time. Relative compared to a resistive heating electrical appliances such as a electric cook top.
I'm trying to learn to be re tired where time can slow down a bit. Should my morning coffee get cold, I have the time to put it in a pot for reheating .... or buy an insulated cup.... or go over to Master Coffee Jim Bennett's for a proper cup.... even if you are camping in San Diego.
I can't help it ...... I grew up reading Popular Mechanics in the 50's and 60's .....