hard or soft- depends on what you need the liner to do.
I hauled 3 loads of rock at about a ton each in my chevy. Shoveled it in AND out!! I was going to school in FL at the time and it was almost 100*F out. The Line-X in my truck never snagged the shovel or showed any wear after all this abuse. Rhino will tend to tear under this kind of use, and I don't even want to think of what a roll-on might do. Rhino is useful if your need is more to hold things in place and prevent minor scratches and such. Line-x is a MUCH tougher material, but stuff slides on it pretty easily, especially when it's cold. Although, I have found that if I put my tube sand in while soft and thawed, when it freezes, it just about bonds itself to the line-x. Doesn't move at all! I got line-x on my new truck and will likely never get anything else.