The factory Mopars are the shortest, have a inexplicable cavity that allows dirt and debris to enter and make the most contact with painted surfaces which they will rub off over time. Honestly garbage, stay away.
The best ones are the Husky, but I would team them up with a set of running boards if you want actual protection, especially from rocks being thrown up from the front tires hitting the rear quarter panel and chipping it (especially the rear painted fender flares get chipped), which is very common due to the wide hips on the RAM.
If you don't like that option, it's highly recommended you PPF the lower sides and rear front quarter of your bed for rock protection. I personally have the front Husky guards and factory black running boards. I rather have a clean look, but the Husky look good and only cost $40 or so for the front set. I got my OEM boards for $100 from a local seller. Much cheaper than $900 or so for PPF.