Bullets, eh? Fortunately that's not a problem in my neighborhood. Might try that to protect windshield from rocks.
I'm seeing a bunch of different things marketed as POR 15. Anything from "chassis coat paint" to "top coat" Is there a Real McCoy?
That said, how about grass? Does it simply not stick or does the POR 15 make for better release when spraying? I experimented with cooking sprays on my snow thrower. I'm going to try the POR 15 on my newly purchased ancient Woods mower and a trailer I picked up. Top is immaculate, but the axles need a coat of something.