I'm not worried about doing it. I worked as a powder coater for 2 years, and learned how to wet paint there too. The best option for a smooth and tough finish on a polished surface is to clean it with a light solvent, rough it up with a bit of 240 or 400 grit sand paper, clean down with a solvent again, then pass over it in light layers, however I'm after a slightly imperfect finish, so I'll rough it up, then use one or two fairly heavy layers, and maybe pick out some details with highlights and wear. I was just worried about the legal aspect of it.
Thank you for the heads up on the design flaw too, that's a useful thing to know about.