I just called Tremclad in canada, and once i told them that i painted my cars with it they said "are you the guy with the cars on the internet, the orange ones?" funny they knew all about me!!!! i hope i get some royalities if they market this product!!!! anyways, they did mention that the rustoleum and tremclad are both alkyd based oil enamels. and that they are basically the same product and labeled for the us, but they are made in different plants. they said that the paint should dry fully in 14 days, but mineral spirits actually slows the drying process. however they are basing this on very heavy coats, typically saying that full coverage is acheived in 1 to 2 coats. but when i paint i don't get full coverage until on or after the 3rd coat. with aprox 6 coats in total, i think my layers of paint would be less then 1 heavy coat of the tremclad when you also factor in wetsanding. but i really think they don't know when painting on cars, since they never really tested it. they also mentioned not using any hardners, that it is not designed to be used with the paint. what all this means to you rustoleum users i don't know, but they said that the 2 are very simmilar products if not the same. also i know i'm repeating myself but, no matter what you paint using any paint even automotive (like singel stage acrylic enamels) they all take 3 months to fully harden, and that's exactly what i've noticed with the tremclad AND all 6 single stage paintjobs i've sprayed on over the years.