Sherwin Williams Jet Flex
I am planning to use Sherwin Williams Jet Flex on my RV-9A but have not done so yet. It should be applied over an epoxy primer, see the SW data sheets.
Be aware that there are two formulations of Jet Flex both of them polyurethane, one is a solvent based paint, the other is a water based paint. I'm leaning towards the water based as it is supposed to be less toxic. You need to wear a good mask for both and paint outside if you don't have a booth.
FYI if you want to match the Cardinal Powder Coat T009-GR230 light grey (RAL 7035 is the european color match code) that Van's uses to powder coat the steel parts here are the Sherwin Williams paint codes:
Sherwin Williams Jet Flex (solvent) L09511
Sherwin Williams Jet Flex (water reducible) WR P09511
Note these are both semigloss to reduce reflections.