I am thinking using a bedliner underneath cab floor. I am thinking about using Line-X, Inyati, or Rhino-Liner. However, I saw an add for Helculiner this weekend and I am thinking it will be a lot cheaper to do it myself.

http://www.herculiner.com/

Has anyone used this product? Or should I just spend the $$ and get the job profesionally done.
Any advice or experience would be greatly appreciated.