The least expensive but excellent hitch is probably the mid-grade Reese, which they now call the Select Plus. I used one of those for over 10 years and over 100,000 miles towing my 5er. DO NOT
go for the el cheapo Reese "Pro Series", but look for the normal Reese Select Series 20k 5er hitch. Like this one:
Reese Select Plus 5th Wheel Trailer Hitch - 20,000 lbs Reese Fifth Wheel RP30081
Note that price does not include the "install kit", which includes the base rails and the hardware to bolt the rails to the frame of the truck. The install kits come in two flavors, standard for about $125 and custom "quick install" kit for about twice that. The difference is in the amount of labor required to install the kit. The standard kit requires the installer to drill holes in the side of the frame, while the custom brackets use holes that are already in the frame. Drilling those holes is a bugger dog bear of a job. The only reason you care which one you get is the cost of installation. So have your pro hitch installer decide which would be the least expensive overall and go with that one.
The disadvantage to the Reese Select Plus hitch is that the bed rails are on top of the floor of the bed. Some people insist that nothing is left in the bed when they remove the hitch. The above-floor bed rails are only about 1/2" thick, so they don't reduce the capacity of the bed enough to worry about. But some people will pay a lot extra to not have those rails in the bed when the hitch is not installed. Reese makes the Elite Series that takes care of that concern, but you saw the price of those things. And the install cost for the under-bed rails will be a lot more than the cost to install the "industry standard" bed rails.
Lots of folks in this thread have endorsed the B&W Companion hitch, which uses the hole for a B&W Turnover Ball gooseneck hitch, so there's nothing but a hole in the bed when the Companion hitch is removed. But those cost a lot more more than the Reese Select series too:
B&W Companion Fifth Wheel for Ford F 350 Super Duty, 2014