We are buying a new microwave and have a cabinet under a small cupboard that we built specifically for the microwave when we built the house. A salesman told us that they had changed microwaves in 2011 and to now put a countertop microwave into a cabinet is a major fire hazard. According to him we must buy a much more expensive built in microwave to put in that cabinet. The cabinet can fit a large sized microwave with 2-3" of space on each side and 4-6" on top. I cannot find anything on the web that verifies this so want to know if this is true or not.