I did the roll on bedliner myself in my old Ford Ranger truck. I had to do it twice. The first time I used Duplicolors roll on bedliner. It started to peel off so I then removed what was left of it and then used herculiner. The herculiner held up I didn’t have any peeling. I also used it on the lower part of the body after repairing some rust. It worked well enough I used it again on my next truck, a Ford F-150. I didn’t have any peeling on that truck either. The only problem I had was that it started to fade really quick. At the time they sold a UV protectant top coat made by Herculiner. I applied this and it looked like new again and never faded again. I had it on this truck for about 8 years. I did have a bed cover on it and a rubber bed mat.
The prep work of the bed surfaces is what makes it last. You have to make sure it is really clean, every square inch and nook and cranny. Then you have to scuff the paint so there is no glossy parts left. I used a 3m scuff pad made for this purpose. If you have any bare metal, sand it and coat with a good primer/sealer. After all this you clean again with a good wax/grease remover, I used a PPG product. Most of the time it takes to do this job is the prep work. It’s not a 2 hour job, I don’t remember how long it took me it was a long time ago.
Would I do it again? Probably not, even though it worked for me and looked good. It is pretty thin once put on, more like a textured paint. This was all I could afford back then. I would do the line-x product.