I've used it before....
I painted the roof of my van with aluminum mobile home and roof coating,when I got tired of doing it every year with regular enamel--the heat peels paint off in short order,but the roof coating has held up well,only did it twice in 10 years since I did it --the stuff doesnt harden real solid,it stays flexible enough to stretch and shrink with the steel when it expands and contracts,so it wont crack---I dont think I'd use it on a truck bed or trailer floor,it would get scraped off rather easily--and I used some to seal concrete poured in the arches of my quonset hut garage,and it didnt adhere,you can lift it off in big sheets--it does stick very well to metal,wood,and other materials though..
I'm not sure it would perform any better than regular rubberized undercoating,but it is much cheaper,and no worse--the other types of asphalt emulsion roof coatings and foundation coatings might work even better--many contractors paint underground pipes and tanks with the black roof and foundation coating before burial,and I have seen 30 year old oil tanks unearthed that were still like new,and the coating still intact--its nasty stuff to work with though,I dont think you could spray it,even with an undercoating gun,you'd have to brush it on---R-M paints usued to make a "chassis black" paint that was basically the same thing,it said to thin it with gas(!) to spray it--I think Limco bought out the R-M paint line......
I bet I've tried everything known to mankind to prevent my trucks from rust,and guess what--mother nature always wins!!--despite all the undercoatings,POR-15,drain oil,grease,paint,roof coatings,driveway sealer,and many other things like linseed oil,white lube spray,etc--they ALL slow it down,but so far nothing I've tried stops the salt induced cancer,all my trucks in the past have rusted away despite my best efforts--I think a good bath of drain oil from a diesel engine with a spray gun is the best so far,but you must apply it every few months,and get used to turning black with soot every time you wrench on the truck!!--but its cheap,if not free,and effective!...ever notice how the ONLY rust free spot on a GM truck is where the transfer case heaved 90w all over the floor in the middle of the cab??
