Just to clarify: The Mor/ryde IS is just a little more than an upgrade. It's a total removal of the OEM suspension and a complete install of their system which included shocks at all four wheels.
We're on our third fifthwheel and we've had the IS and Disc Brakes on all.
Michelle & Ann
2018 Chevy 3500HD Crew Cab High Country DRW, D/A, 2016 RW39MB, Dual ACs, Auto Level, Auto Sat Dish, Stack W/D, King Sleep #, 17.5" Sailuns w/Disc, MORryde IS & Pin, Comfort Ride Hitch, 5.5 Onan, Res Fridge & Induction Cook Top