We have a 39' 5th wheel and never had a problem in any site we were given, I will say that your backing skills can sometime get tested, I drove tractor trailers for almost 30 years so that has really helped my me, good luck and just take your time.
A lot of the time it's not the driver's skills that are at play as much as vehicles parked too close to the road (or into the road space). Of course, it seems like the times that has happened to us the 'owner' is no where around!
We have a 34'MH and have that problem sometimes and dh has a time just avoiding other's vehicles + posts/trash recepticles, etc.
We always stay in loop 100 and so far have been able to maneuver around the obstacles!
I always like the sites with an RV, two vehicles, and two golf carts.