x2 on the Adam's Quick Sealant. I use it on all the plastic and rubber trim, running boards, and Line-X. I apply it quite often to the whole front end to keep the buggies from sticking.
In this photo, both the silver part of the lower front bumper and the skid plate were coated with Line-X Premium. However, only the Line-X on the bumper was getting sprayed with Quick Sealant. I never really noticed the difference until I looked at this photo, taken with the sunlight direct and low. You can see how the un-sealed skid plate is much lighter than the bumper.
Rest assured, I got out the creeper and coated that skid plate good, so it is nice and dark. Also makes washing the mud of that much easier.