When I picked up my 5th wheel 250 miles away and towed it home I had chucking. I had an old used Reese as a 5th hitch at the time. After getting it home I loaded it with all the normal camping stuff. Towed for a while and still had chucking.
Ditched the old Reese and got a B&W Patriot. Still had chucking. The B&W is set as far forward as possible and the 5er is 1/2-1" nose high with a 20% pin weight.
Used the B&W for 3 seasons. Chucking was off and on depending on road conditions.
Got tired of lifting the B&W out of the truck so I thought I'd give the Andersen a try. Still have the same chucking on the same roads as I did with the old Reese and the B&W.
Way too many factors involved for a one size fits all solution IMO. My 5er is short @28'L so I think that may have something to do with it. It only chucks on bigger bumps and over passes. On smoother roads it's great. Once in a while it will almost go into a non stop chucking mode when on concrete freeways where the undulations are pronounced and are numerous.
FWIW I also added a MORryde pin box. It alleviated some but not all obvious chucking. Added shocks to the 5er also. They did nothing for chucking.
I stand by my theory that its my shorter 5er and truck combo wheel to 5er wheels spacing, since I've done everything possible to alleviate the chucking.
Not going to drop big $$$$ on an air ride type pin box or 5th hitch. 80% of the time it tows great. I can live with that.