I had a Line-X sprayed into my last F250. It was over 14 years old when I got a new truck, held up great, not slippery when wet or loading the motorcycle in the bed. At the time, I looked at both Rhino & Line-X, and liked the texture and hardness of the Line-X better. That was back in 2002.
The current F350 has a Ford factory liner, looks like my old Line-X.
The key is making sure the installer does all the prep work. Scary to watch them sand off the finish on a brand new truck bed! Then they need to know what they are doing in applying the liner properly. They removed the metal tailgate cover, sprayed it, and put it back so it could be removed latter if needed. You may want to have them remove the bed mount bolts, so you can take them out latter if needed. Ford sprayed over them, but I never took them out of the old truck, so probably a better seal. Unlike a drop in liner, you don't get rust underneath, and the texture keeps them from being slippery when wet.
I wonder if there are any issues spraying the new aluminum beds?
Only complaint with the Ford factory job, they use a textured plastic cover on the tailgate. I'd much rather have a sprayed metal one.
2013 V 3105
2016 F350 King Ranch CC 6.7 diesel dually