I used the Easy-Off. It works but as you said it is only a "one and done" type of solution. I used purple power but nothing happened. Some people say you can use it but that's not Castrol or Super Clean. When I used it nothing happened. Purple power is basically just a household cleaner like Mean Green or Simple Green. also the Easy-Off takes the paint off and leaves a white residue. I don't know if it's crazing of the plastic or if it's damage to the surface. I have yet to sand to see if it removes this discolouration.