I have the 5er/GN prep package and purchased the picture frame adapter and attached my existing Reese 20K Signature hitch to it...No problems.
I don't know about your existing hitch, but it should fit, I think, the picture frame adapter. Reese makes one for a little over $300 , free shipping. I do like the new hitches that they're coming out with that will fit in the puck lock downs in the truck...your call..."IF" your existing hitch WON'T work with a picture frame adapter, than it sounds like one of the three you mentioned, though more expensive would work best for you.
I don't know about "torquing down" the T-locks....I had to adjust my picture frame adapter a little, then it locked into the prep package and I haven't touched it since.
Hope this helped...
Jim
Jim & Kathy, (Boxers, Buddy & Sheba)
2016 Ram 3500 DRW Longhorn 4X4/CC/LB/Aisin/4.10/rear air assist ...Pearl White.
2016 DRV MS 36RSSB3/ W&D/ slide toppers/ DTV satellite/ 5.5K Onan propane gen.
B&W RVK3600 Hitch
Fulltiming in WV & TX
USAF 71-75 Viet Nam Vet