I'm a relative newbie with my porter-cable but figured I'd post this success story - my neighbors' Toyota Highlander got sprayed with white spray paint on Halloween (what ever happened to shaving cream & eggs??? kids are pricks these days I guess). Anyway he's seen me messing around with my car and asked if I could give it a shot. I wasn't sure if I could get it off - tried the clay first but that only removed it in a few spots where the spray was thin. I used 3M Fine Cut compound with an orange pad and with fairly heavy pressure, removed all the spray paint! Was suprised on a black car that I didn't leave much hazing in the process, but followed with 3M Hand Glaze and AIO just to make it look pretty. Took 45 minutes in all, here's the pics:
BEFORE
AFTER
BEFORE

AFTER
