I recently installed dual liner on my 2011 short bed. I decided to go with it for the combination of the zero slip bed and the fact that I can remove and put it back in a half and hour. Mat is very thick and fit of sides and bottom were perfect. Sides are already predrilled for tiedowns. I ordered by phone direct from manufacturer and was treated extremely well. Ordered on a Monday and received it on Thursday. Sprayons look the best if done right, but don't offer any dent protection. Also once you do it there's no turning back.
The bed mat is a very thick rubber with nubs on the bottom so no scratches. There is a u shaped channel in the sides and bulkhead that the bed mat sits inside, I suppose in a heavy downpour water might pool up, but it would dissipate quickly. I have an extang fulltilt tonneau so it is not a concern for me. Good luck.