Because of posts on here that 36' was the max so I bought a used 36' DP. Did not take long to learn 36 max was BS, especially in the West. Traded for a 40' costing a fair amount and once we could use more than 100 days/year bought current rig slightly used...again costing $$$. Buy more RV than you think you need ONE TIME!!!
We mainly stay in USFS CGs BUT do not show up Friday hoping to find a site big enough. Not sure who determines the max size in CGs as I'm usually able to get in even when it says 30' max.