I'm pretty sure it will stick to plastic. They spray it in wheel wells and even on interior floors of UTV's.
I don't think it would be a bad idea, I just think it might be pretty pricey. Just guessing maybe $150ish for a rhino lining rep to spray it. I've also heard their quality of application can vary wildly. The guys that did my truck bed years ago did a decent job. Think it ran me just shy of $350
My neighbor has a Rubbermaid lawn cart, pretty much the same material as the Pioneer bed. It's maybe a dozen years old, and has worn miraculously well.
I personally use a tarp for covering the top of a wood pile in the bottom of my bed. It's thick and durable. Ran me $8. I pull that out, shake out the debris and run a shop vac around the bed before folding up my seats. Then I just stow the tarp between the tailgate and seat backs. Has worked great.
Bed mat (2P)
Manufactured from rugged vulcanized rubber compound. Tight, contoured fit, Pioneer branded.
Dealer installation charges may apply.
Poly Bed Liner
Manufactured from ultra-rugged HMWPE (high molecular weight polyethylene) - extremely durable. Provides protection to the bed and rear seat area. Allows for easy unloading of dirt or other materials. Molded side slots enables use of partitions. Quick installation, quick removal. Available Mid December
Dealer installation charges may apply