I believe which way you go depends on why you're doing it. If rust is your concern then dipping is the answer. It gets rid of everything that isn't solid metal. I had my Pantera dipped about 20 years ago because I was concerned there was rust where I couldn't see it; inside frame rails, etc. Modern dipping techniques are great at neutralizing all the chemicals and then protecting areas you could never reach. To this day, I've never discovered a single spot where one of the chemicals used in the process leaked out over time.
My Pantera came out of the chemical bath as a clean shell with only a couple of rust spots in typical areas such as a silver dollar sized hole one rocker panel and some small holes in the rear, inner fenders. I've seen other Panteras dipped that didn't fare so well. I saw one Pantera that came out of the tank looking like a lace doily. Literally every panel was full of holes. The owner wasn't a happy camper!