You have to be careful using any kind of rattle can primer. I have had rattle can primer lift when the top coat is applied. Try the rattle can stuff, but then a sealer over it before any primer/filler or top coat. I also don't completely rely of primer/etcher to make sure there is no rust buried. I first wash the exposed metal in a rust preventor, and then I prime. In any event, remember that primer will not hold up very long against oxidation penetrating it.
