Seeing that the times have been very close as far as drying times....and the scratch results differ, me tends to think that maybe the EPA has stepped on the Rustolium, in the regards of chemical makeup. Years ago, I've shot Rustolium over bare metal and given a month of drying time(if surface was clean and prepped), it's a very durable paint..as the painting was part of my brothers business(Tigtoons) I'd still give the Rustolium at least a month to dry to prove itself. The Tremclad might be a different chemical makeup as stated above....so it might be just a better paint for this type of application. Our government at work.

Did you know you could be "fined" via our EPA for shooting your car in your garage......but roll it outside, and they can't do a thing.