There are so many variables right down to driver ability.
Our 'home' CG is a MD SP. Biggest sites listed, most all of them, is 30'. We are 35'10" LOA & over the years have been in just about every site with no issues save for a couple of them.
Generally speaking across the country we have not found a 30' limit CG that didn't have at least a few sites very capable of accommodating us. Most CG offices that assign sites will tell us to go look, setup, come back to pay & fill in details if their personal knowledge of each site is not that great.
We never request a pull through. The 'lookers' don't bother us while we park. The DW spotter is excellent. No shouting. No dancing about. No standing around doing nothing. We know how many paces the 5er is long & can pace a site very accurately.
The biggest problem found is going into a NP or SP & finding a small class B, a TT, a TC, a car & tent, or a small C in one of the few long sites.
US RV base, MD
2007 Alpenlite 34RLR