I have 3 generic frames at the house. All came UD or 3k matte finish and I added some vinyl decals to them. Pretty easy to pull the decals off if I want to change up the color.
Peter did paint some rims for my wife's bike though. They look fantastic, color matched perfectly, and have been holding up great too. I would definitely let him paint my stuff in the future. For the cost, it just isn't worth the hassle.