The next time you are looking at MHs stand back and look at the profile.If you put a long box on a short wheel base the over hang in the back is more likely to wag. However, the short wheel base is easier to drive around corners except the rear swings out more into the other lane when turning. On the highway and in wind the longer wheel base gives more stability. Manufactures can save money by putting a shorter carriage under the MH and extending the rear frame out behind the rear wheels. Installation of a rear trak bar will help prevent sway or wag. The trak bar goes from rear axle housing up to the frame on an angle to prevent the wag. If buying used I would be looking for the after market that were installed. By the time sway bars, trak bar and steering control is added it can add up to $$$$.