I have a 2002 Audi A4 which has "automatic-dimming outside mirrors" and a heated defog fuction according to Audi. I have some water-spots on the mirrors that are not removable with normal glass cleaners/vinegar. Would it be safe to polish these with the PC and something like Autoglym's Glass Polish? I'm not sure if these types of mirrors have some type of coating on the glass. Would using a more aggressive polish possibly damage the auto-dimming function?