dont like drop in liners. like said above, they trap moisture and rot the bed.
aftermarket spray on works but you have to get a good installer.. proper prep and quality materials/product
factory liners are usually thing but they seem to hold up well for most people
this is discussed on every truck forum and it seems like a 50 50 split between line x vs factory.
me theory is that both of them work and both of them dont work
it really depends on what you are using the bed for
If you are using it hardcore heavy duty i don't think anything will last and you have to expect to respray it when it get damaged.. its a liner afteralll and you cant expect it to be invincible.