mine are ceramic coated, love the look ,
had them all fitted and placed in the car for bot low and tall decks
then sand blasted then coated .
have had other guys painted with high temp paint and put in oven to cure, and they have held up very well over 6 years with not much fading ,
i dont do spray can as this just doesnt work usually blows off quickly.
as for scratching any can scratch , the good about ceramic i can rub it a little with mothers and its gone .
prep is the secret here,as well as oven temp!! dont do infered lite
at all