anybody ever use spray on bedliner?

well the reason i was thinking of using it in the first place was to cover up the unsmoothness of a product that i used called rust bullet....i talked to my local paint supply guy and he also said that he doesnt think it can be painted...i think im just going to return it and buy some rocker guard...i used it on the inner rear wheelwells after i finished my tubs and it turned out good, plus i think it is paintable....i just need a durable tough finish to cover up the rust bullet since it didnt exactly go on the smoothest (dont ask lol)