I just purchased a Samsung HPR4272cx...awesome display btw. Anyways, the salesperson at futureshop says that the fans in plasmas need to be cleaned of dust every year (even though the Samsung is fan-less?). If this isn't done then the display will overheat and this is not covered under the manufacturers warranty. Is this true or just a scare tactic to get me to purchase their 'Product Service Plan', thanks.