Not sure upper stableloads are right for me (UPDATED)

I think upper stabilload are the safest reinforcement you can do.
I can't stand the image of lower shims applying breaking force on the leaves.
My F350 dually did not sag with heavy camper to the degree to apply load on upper overloads, but just to be on safe side, I put hockey pucks there.
Just because I am not hurting anything by doing so.