Sherry,
In the link above, they are installing a stabilizer bar on a gas motorhome with a leaf spring suspension, this application has nothing to do with your coach. In the reference to an air bag suspension, they are installing an aftermarket self centering shock absorber between the steering linkage and the frame as a steering stabilizer. This has nothing to do with a stabilizer bar. Your coach did not come with a steering stabilizer, but if you want to add one, I would recommend a Safe T Plus over the Roadmaster.
If you are going to trade the coach off, there is no reason to spend a lot money on aftermarket parts to make the coach drive better. Just find a reputable shop like Iron Horse in San Antonio, and have your steering problem fixed, assuming that you even have a problem. There are a lot of people who think that a coach has a handling problem if they have never driven a long wheelbase coach when there is really nothing wrong with it. All coaches need steering corrections while driving, some more than others, but they do not drive like a car where you can take your hands off the wheel.
Gerald