Por 15 vs. KBS Rust Seal

All I can say about POR 15 is I used it on my Barracuda back in 98/99 and no new rust has developed where I put it on, it's never pealed or shown any signs of breaking down. I had some left over and used it on the steel bulkhead to my basement then top coated it with red hardware store enamel. I have not had to touch it since in 11 years of New England winters. Prior to that I was wire wheeling the bulkhead every spring and putting a new layer of rustolium on it.