I don't like to use the microwave to thaw stuff all the way, but I use it frequently to hasten thawing. My nuker has an auto-defrost cycle - enter the meat type and weight, and it is supposed to thaw it. It doesn't work that well, and tends to cook the meat around the edges, but if I cheat and enter a weight that's lower than the true weight, I can finish thawing in the fridge and save two days or more. A frozen butt might take four or five days to thaw in the fridge, but a partly-microwave-thawed butt might take only 1.5-2 days. Or you can partly-thaw it in the nuker, then finish it in the sink with a trickle of cold water from the tap.