I have Ricksons on a 2000 F250, and 19.5" tires. It rides just as good, if not better with the 19.5" tires, definitely not a softer or plush ride, but very comfortable and handles well. 19.5" wheels and tires are bought primarily to achieve a greater safety margin with heavier loads. My application of SRW pickup with a slide-in camper is a prime example.
Rusty