Chaps,
Thanks for the additional information. I popped up to see a local powder coaters and I decided not to do it at all! Why? Well, my lower track control arms still have the ball joints crimped in so I can't remove them and didn't want to cook the grease that is inside. The hubs still had the old ABS/hall sensors in place and had already had the new bearings pushed in. Again, don't want to damage any of these. The anti-roll bar still had it's powder coat in good nick in the middle and I didn't fancy sandblasting that all off to then powder coat again. So...I'm rattle can spray painting them all with two coats of red oxide, two coats of black. I'll waxoyl and maybe stonegaurd after to give the top layer "plasticity" that I wanted from the powder coat.
Prior to this visit I did a little more digging regarding my initial question about powder coating onto the Vactan:
I called a company called "Plascoat" who just so happen to be based in my home town of Farnham. I blagged my way through the telephone system and got speaking to one of their technical gurus. He said that powder coats "key" onto epoxy or acrylic based primer/base coats as they are solvent based. Vactan is "a vinyl acrylic copolymer and tannic acid". Well a copolymer is an epoxy as far as I am aware (excuse me if I'm telling a porky here) and it clearly states that it's acrylic based so the chap advised that Vactan should be fine to powder coat on to.
Anyway...