Depends what you're looking for.
Spray in for trucks that get used, but not abused (don't care what kind of spray in it is, if it's a heavy const truck there are things that will gouge/slice the best spray in) and the bed is exposed so you want a decent look and rust protection.
Plastic bedliner if you want to preserve the integrity of your bed and you beat the crap out of the truck bed. You can get plastic liners for very cheap if you go to a spray in place, they have take-offs laying around usually.
Throw a rubber mat on top to keep stuff from sliding around, can pull teh mat if you WANT something to slide in (like a sled).
Plywood if you want a disposable surface that can take a hit from dropping heavy stuff into the bed.
No bedliner and a rubber mat. Keeps stuff from sliding around.
The last one is what I've had in almost every truck I've owned, but I'm too cheap to get a spray in liner and most of the time, there's a tonneau cover or topper on the truck.
