We are on our 4th MH now. We have had a diesel 34 footer, a 36 foot diesel (Itasca Horizon), a 40 foot Damon Essence diesel and now this 40 foot Newmar gasser on a Ford F53 chassis.
The 34 ft diesel was the worst ride and the 40 ft gasser is the second worse. The 40 foot and 36 foot were on Freightliner chassis and both had a great ride, with the 40 footer slightly better.
I think the airbags, length and weight make the bigger diesel coaches the better ride.
Phyical problems makes the gasser a necessity because of the handicap features of a wheelchair lift and HC bath.