We went from a Weekend Warrior toy hauler to our Arctic Fox truck camper. We can still bring toys with us in our enclosed trailer or leave that extra length behind when we don't want them.
We never had problems with gasoline sitting in the carburetor because I ran the generator twice a month. The LPG runs cleaner than the gasoline units and now you do not need to worry about stabilizing fuel or other additives.
Get the SuperHitch receiver and SuperTruss extension if you plan to tow anything behind your new combination. Our enclosed trailer varies in weight based on what we bring 6000-8000 lbs.
We were spoiled with the amount living space and large tank capacities of our toy hauler. I think this will be your biggest adjustment going to a truck camper.