I've owned four different large Lance campers in the last 20+ years and used the old style Happijac tiedowns on a Ford in the mid-80s, Torklifts in the 90s on Dodges, and now back to the frame mount Happijacs on my '03 truck. The Torklifts I had for the 2nd gen trucks wouldn't fit the '03 and the Torklifts that fit the '03s interfered with the fuel tank fill door so I installed to the frame mount Happijacs.
I haven't had any problems with either the old style Happijacs, the Torklifts, or the latest frame mount Happijacs, or had a problem with camper movement in the truck bed. I've always used a rubber bed mat under the camper, spring loaded front tiedowns, and the Lance camper guides.
Bill