Michael,
I have been a long term lurker on the live aboard site at Sailnet and many of 
the owners there use this particular cheap brand of microwave and have 
reported great results, even in salt water exposure. When they do stop 
working, it has always been because the single control stops working. They 
have shown to be very useful and last about three years even with the crappy 
power usually thrown there way on some boats.

Rummy