RE: plug finish?
I've used gray for my plugs, some people like black or white.
You'll want to use a quality urethane primer before painting, then a couple good coats of paint. After that, you can buff, going from hard polish to super-soft "shine-maker" polishing compound. Make sure to use clean rags to buff.
An alternative is to spray urethane clear lacquer or clear coat on top of the paint to further protect it. I've also found that clear coats develop a much better shine if polished well.
Oh, and remember - an extra half an hour of quality put into the plug will mean an entire hour less of work needed on the final product.