The Impavidus fit-out looks great.
On our 2009 Bav 38, we ordered a microwave as part of original fit-out.
The options were a cupboard above the refrigerator or a microwave. It fitted this space perfectly. I don't know if this applies to your boat.
Be aware that the wattage shown on microwaves is not the current they draw, but the power of the actual microwaves. When at anchor we use the microwave on a 600w setting rather than the 800w setting, even though our inverter is 2000 w. We do have 440amp/hr of battery capacity to run the inverter as well. There appears to be a high current draw judging by the drop in measured voltage. Our inverter is wired direct to the batteries so the battery monitor doesn't display the amp draw.
The microwave has the single biggest draw of any of our electrical appliances. We use gas to boil water and usually use the gas toaster.
I could not get any proper conversion information on input wattage compared with output watts.
Microwave is great for heating food on long passages.
Craig
"Shirley Valentine"
Gold Coast
Australia