I need to put some sort of protective coating on the steel underside of my project car. I see that have choices of spray can undercoating from $1.99 Advance Auto crap up to the 3M gold plated stuff. Then someone said think about Hippo bed liner material. Good? Bad?? Lousy idea???

I'm for sure not going to use the $1.99 stuff and I really dislike buying any overpriced 3M products just on principle .

Since there are always good ideas from others here, I'd like to hear them as I'm just about to jack the body up on horses within the next few days, clean off the surface rust, epoxy prime and have at it