In my opinion, poor MV carrying around trash that is probably leaking in the walls through the roof, corners, AC, or windows. Also on my opinion they want to justify using a MV as a camper/RV one needs to build something better than what the market manufacturers for the mass.
One accidental bump into anything off-road with that 5th wheel on the back of a MV and you have a mess to clean up. Pretty sure that MV can articulate more than that 5th wheel frame could do.