When you compare apples to apples, the 5er is cheaper to purchase. Keep in mind, the front 4-6' of a MH is basically lost space once you park. Also a $125k 5er is probably equivilent to a $3-500k MH, so even after adding the cost of a truck, you are still way ahead.
In terms of maintenance: Again the 5er wins. You can take a pickup into any autoshop and they will know how to handle it. With a MH, you often wind up going to specialty shops and buying specialty parts with specialty prices.
Fuel economy: From reading various responses over the years, a 5er can expect 10-12mpg and MH's run 5-8mpg. You will be hard pressed saving enough fuel driving the toad to cover the balance out the extra fuel the MH uses. Plus half the idea is to set up the rig near what you want to see. If you are driving huge distances in the toad on a regular basis, I suggest finding a campsite closer to what you want to see.
Set up: We can be set up in just about the same amount of time as a MH. Then again, it's not a race. Especially if you are using it regularly, you get in a rythm and it takes us 10-15 minutes on either end without rushing. If we had automated stuff, we could probably trim that down. Also, if you pull a toad, there is no backing into a site until you unhook, negating the supposed benefit. I always find it funny that people seem to be afraid to leave the rig when setting up as if that's an advantage. If I don't feel safe getting out, I'm probably moving on to someplace safer. If it's raining, I can just plug in, drop the legs and hang out in the 5er in total comfort until the rain lets up in just a couple minutes.
I'm hard pressed to find any significant advantage to a MH over a 5er except as someone mentioned, "you look cool driving one". The exception would be if you get one of the small class B units and skip the toad. Then I can see some advantages for being able to be on the move quickly but it comes at the expense of having to tear down the campsite every time you want to go to the store. In that case a truck camper may be a better option, as you have the option to drop the camper at the site getting the best of both worlds.
Tammy & Mike
Ford F250 V10
2021 Gray Wolf
Gemini Catamaran 34'
Full Time spliting time between boat and RV