Painted the scoops on the Swinger Rustoleum satin black

There's nothing wrong with Rustoleum, it's cheap and it does hold up. I used Rustoleum on several of my cars for different things over the years and it works great but it may start to oxidize on you because Rustoleum has no UV protection, if you keep them waxed often you will have no trouble. My uncle painted the running boards and bumpers on his 50 Ford F-1 with Rustoleum semi gloss black over 7 years ago and they still look great but he has to wax them every month or so to keep them from oxidizing. He still takes 1st or 2nd place in every show he enters it in.

I usually thin the Rustoleum with about 40% mineral spirits and it spays great, but that is with a standard gun not a gravity feed.