Anyone had air duct cleaning done? In selecting a company to clean our carpets, this is a service that they pointed out. It costs more than cleaning the carpet and according a quick review on the web, the EPA is neither pro nor con on it. Just wondered if anyone had an personal experience. Our house was built in 1982, has central gas heat and central air, and we have never had the air ducts cleaned. Have noticed no real problems, but don't know that we would have. Thanks!