As I posted above, POR can easily be painted over as long as it is done within the time-window described in the instructions.
We have also sanded it (after it has set/cured) and then used a PPG sealer/surfacer before painting with PPG DCC urethane. It has lasted nicely for over 10 years on the roof of my Suburban. This application was out of desperation - the roof was heavily pitted. All paint had been removed and all rust had been removed - we were still worried about the pitted metal.
We will soon be using it on my COE's frame. One coat POR, followed by a coat of PPG DCC urethane black with a little flattener.
As posted above, POR is messy stuff. Also, you have to carefully follow the instructions.
