POR-15 Opinions

[Ian71GMC]

In about three weeks from now, I'll be taking off my piece of junk 8ft fleetside bed to swap it for a flat bed. The flat bed is currently my uncle's, but he doesn't want it anymore, so he's giving it to me. You can't pass up free stuff. But before the flat bed goes on, I need to take care of my frame. So, I plan on grinding off all the rust and painting it. I don't have the money at the time to have it powder coated, so my question is: how have your experiences with POR-15 gone? Time, effort, application, and results? I've heard it's best to paint it on like painting a wall, but I want some opinions on it. Any help is appreciated.