I remember posting in another list to mention that I had painted the exhaust headers on my vintage street bike with flat-black, high-temp paint.
No flames, but some shock - I guess that's what you get on a vintage bike restorers list.
What these restorers didn't realize, I suppose, is that there is a class of objects that are used, daily, as they were originally intended.
My exhaust headers (and the cast-iron cylinder, next) are black because that motorbike is used to take me from one place to another, and the original chrome just wasn't protecting the metal anymore. So, if it's either rust or paint, I pick paint.