Thanks for the comments everyone
I use enamel paint mainly, but use a spray of dullcote or similar when I'm finished.
For the main part painting Robot Heroes is super-easy. There's a thread in here of all my Robot Heroes customs called something like "snaketales smorgasbord"... check it out http://www.otca.com.au/boards/showth...ht=smorgasbord
No airbrushing: I hand-paint my customs.