I have a Rieco Titan dolly and it is really heavy duty. It is on the second camper...
Mine is the 6' version and I used it on my old 8' long FWC Ranger. I had to watch for the floor pack bulge at the rear which was too wide to fit. I just placed it forward of the bulges. On my ATC Panther I had to place it crosswise to the camper.
Currently I built a wood riser on it so that it is the height of my truck bed so that I don't have to raise and lower the jacks much.