The spray paint that you can get from Supercheap works ok, plus theres a huge variety of colours. BUT like what Jamie said it will react with the plastic if a suitable undercoat isnt used.
I tried the 'plastic undercoat' (clear) and that reacted just as bad as the straight colour, but strangely the standard undercoat(flat grey) worked ok.
As long as the susequent top coats arnt too thick, then any kind of reaction with the plastic is minimal.
Theres also a floor polish that apparently gives a fantastic shine, protection and fills in any minor scratches when applying it over the final top coat, I havnt tried it yet, but if anyone wants? I can post up the brand and the method of application.
1993 ED XR6 M5 (1 of 329)
Turbo on the way!!
1993 EBII Fairmont (Now wrecking, PM if you want any parts)
1988 Nissan R31 Skyline