Usually if you ask in the fiver forum you get fiver proponents, and in the MH forums you get MH proponents. :)
We've had both. We prefer the MH but if it is going to be parked for weeks or months, I would say the fiver makes more sense. Or for a one-stop trip, like a week at the lake. For frequent travel we feel the MH makes life better. That is just our opinion based on our experiences.
The ride quality of our truck with the fiver was sort of poor. We were within weight ratings, but still. Over the course of a long day behind the wheel, if the roads were at all marginal (and really, isn't that always the case), I would feel a little beat up. We had a standard hitch and pin box, no air ride etc. If that could be improved, that would help us consider another fiver.
And auto leveling would be a big help. We did not have that, so I had to do the pieces of wood under the tires.
And something that is often overlooked is, is the connected fiver sitting level enough to use as is, on an overnight stop? Or do you have to disconnect to get it reasonably level?
Our fiver rigs were much better in a cross wind than the MHs.
We love having the rest room etc so handy in the MH. We don't use it while in motion, but when we stop, everything is right there.
One thing I absolutely don't miss about the fivers is the cheap junk suspension, brakes, and tires. I know there are brands and retrofits that solve those problems somewhat. I did some of it on ours. But still, the MH has industrial quality running gear, the fivers often have krap. And then there were the fiver frame problems, which I don't hear about as much lately.
Bottom line, if we could know we could get a nice enough ride pulling a fiver, with good running gear and auto leveling, we would consider going back. From the above, I guess you can see that to me the biggest differences are in the driving experience, not the campsite experience.