Anderson Ultimate and aluminum truck bed compatibility

I have been using the Anderson for 3 yrs now, from pavement to oil field roads, no dents or "deflection". Have also used the Curt goose neck fifth wheel adapter plate http://www.curtmfg.com/Category/53/Gooseneck%20%7C%205th%20Wheel%20Adapters as well, when I was transporting RVs, no dents or "deflection" either. This from an actual user of the Anderson Ultimate hitch.