One of the resto shops told me that moisture gets trapped under the aerosol type clear coats and eventually will develope flash/surface rust on the part.He told me this after I had sprayed some of my parts and sure enough after a few months the rust appeared.Of course it was trapped under the clear coat so I had to strip off the clear coat to get to the rust.Now he also told me that if it is sprayed with a gun you're less likely to have this problem.I hope you guys don't run into this problem,but me and a few of my other buddies did.