Earlier in the year, MotorHome Magazine installed a set of SumoSprings on a Ford F-53 Class A Motorhome (2007 Itasca). The article features installation tips and a detailed review of SumoSprings. If you have not had an opportunity to read it, here is a link to the article on www.motorhome.com.
While driving the first section with the SumoSprings in place, the effect of the springs was apparent right from the start. Ride quality was noticeably more quiet and controlled, both in terms of road shock felt by driver and passenger as well as the decibel level of squeaks and rattles. We felt less lean to one side or the other (body roll) on curves taken at highway speeds and in driveways, and more predictable handling in strong crosswinds.