Just the driver's seat back needed repair on my car. Took two days to get the car back after they got the right parts but it took the parts guy THREE times before he ordered the right thing. I don't use the heaters that much. Only the first ten minutes or so until the car warms up and then I shut them off. My advice, if the dealer is willing to replace them all do it because it'll tie up your car until they get the job done so better once than a few times.