Across The Pond, over here in the great Republic of Tejas, a rattle can of Satin Black -neither flat nor gloss- brought my R100S's switch bodies to as-new looking.
Personally, with operating three Airheads for many years, I know what all the switch gear does. I'm also guilty of removing any and all of those annoying "safety" stickers. It's Texas. Call me a rebel.