I say burn the paint off, pour concrete over, then spray that, then a drop-in over that... Maybe even carpet the drop-in

 

Boys I have had several trucks with the lay in liners and what I would do is take out the liner and get several tubes of quality silicone caulking and app;y in to the ridges in a wavy pattern and on the wheel hubs let it dry then reinstall the liner and I would not get no scratches on the pan from the liner. Spray in you will see every dent if you use the truck for what it is meant for.

 

Spray-in for sure, both my trucks are done and wouldn't have it any other way. The cost wasn't that much more over plastic and I'll never worry about rust.

 

I did herculiner roll on myself. Its ok for light use and if you take your time it looks great. If i had the money I would spring for line-x or rhino but for the light use my bed gets the herculiner has held up awesome.

 

I find the plastic liners quite slippery in winter conditions and they also tend to crack. The space between the liner and the box collects dust and grit which acts like sandpaper on the painted finish.
I'd be leaning towrards some sort of spray in liner unless I were loading Ski-Doos or other harsh equipment into the box.