I brought my vehicle to an independent repair garage & the mechanic told me I needed new brake rotors & pads for all 4 wheels, despite having only 6,000 miles on the front brakes and 12,000 miles on the rear brakes. He said the rotors rusted since I didn't drive the car enough (I leave the car at my beach house on Nantucket island all Summer and I only drive it on weekends for a few miles). He said the new rotors are made in China and can't be "turned down" because they are too thin even when new. Do you know of any spray (silicone or oil?) I might use to protect the rotors from rust without affecting the braking power?