POR15
It's the daddy. Seriously, that stuff will be around post nuclear blast long after all the cockroaches have died off.
2 Coats of that followed by 2 coats of 'chassis black'
I've never had much success with HAmmerite, and the problem with powder coating is it seems to chip and flake off, not sure it's tough enough, wheeas the POR15 is rubbery and self healing.