When I at chance I'll add a couple of photos of things. One shows how good powder coating can be, the other how bad!
The 1940 bike I've got looks incredible, shining black paint, glimmering chrome, but a bit too 'bee's, although it does show the quality that can be achieved. The other is an old helmet that was done in satin powder coat. It looks terrible because it's far too shiny and shows every little bit of pitting in the metal. That incidentally is another thing, if it's not a smooth surface you can't fill and sand like you can with paint!
But for a chassis it would be perfect... finish doesn't really matter as it's hidden, and it's a much, much harder finish meaning less scratches and very little maintenance to keep it looking immaculate! Pros and cons