We've had both. The fifth wheel has better headroom and floor space and is basically more comfortable if you go to one place, stay for a week, then pack up and head home.
The MH, especially a Bluebird, is much safer on the road and affords DW the ability to safely sleep enroute to our destination. It is also easier to get the MH into spaces in state and national parks. The MH has larger tanks and more basement storage.
The fifth wheel has better headroom and a more "home like" feel. The MH has a much better frame, air brakes, retarder, and a diesel generator.
Everything in life is a trade off. This is no different.