One thing that I did find that improves Rustoleum is heat. Getting the painted part nice and hot makes the paint dry really hard. I painted a Chevy bowtie and put it over the outlet of my parent's garage radiant heater and I swear that ended up being like powdercoat it was so stuck and so hard. That held up great. It's not practical for big parts but man it works a treat on little pieces.
That's what I did with the fuel door on DogeVan-
I've been satisfied with Rustoleum over the years. Assuming realistic expectations, it does what I need. The driver's door and wheels in the pics below are Rustoleum specials. It isn't nice, but it looks good at 50' and is a huge improvement over the before pic. Of course, the wheels and numbers were changed too.
In reply to Russian Warship, Go Berkeley Yourself :
Excellent, except the combination of pizza stone and offgassing enamel does not seem great to me. I prefer my pizza to be VOC free.
In reply to dculberson :
That's just a Display Photo™
The filler door wasn't hanging off the edge of the rack, either.
Hmmm... if heat helps, how about pointing a torpedo heater at something to big to place in an oven?