Nah....Have you ever noticed the rotors when you get up in the morning after some heavy dew? Or a nail left in your driveway the night before? Surface rust comes and goes in a minute..... (wrc)
It doesn't matter what you do, I work at the dealer and I see Merc Benz come off the truck with surface rust. no worry, if you are concerned paint the rotors and calipers, after cleaning and preping of course, it will look good and no rust.
it's actually a ''semi-protective'' layer of rust. there's no point taking it off: 1) a new coat will form soon afterwards, 2) you're removing material.
