I have a 2500HD GMC and while I love it and the Northern Lite that I carry on it it does limit me on upgrading the camper. Even a newer Northern Lite is too heavy for me.
Truck Payload 1077kg
Current camper 600kg
Looking at a newer Northern Lite that comes in at 1002kg
If I had a 3500 it would be no problem, with the 2500 not going to work once I put water, gear and people in and like others are saying the cost is not that much more. In fact around here the 3500/F-350's are even cheaper right now as many dealers over ordered.