I had a controller go bad as well in the beginning and was told by Flex-a-Lite that it was a batch of controllers sourced from an outside sub-contractor that they knew had gotten into the market. They overnighted me a replacement VSC and I've not had a problem since however I too carry a spare in case I have a problem later. A spare variable speed control module(VSC) is ~$130. So this is not a casual expense to save a few mpgs but I agree that my AC is cooler(not cold) and my trans cooler likely gets a benefit. I also like watching it pull a shop towel into my grille from 10" away. <img src="/forums/images/graemlins/kewl.gif" alt="" /> Brew