POR 15 is a coating, its what I used...its good. The rust converter is just that, a converter, you would still have to use a topcoat.

POR 15 only requires a topcoat if it is exposed to sunlight, or it will turn brown so I hear.

I believe Eastwood has some similar products to POR, but I used the POR and am happy with it....just don't get it on you, it won't come off till the skin wears off....