Hi Bob,
We use Big Rig Best Bets as well because they have a rating for 45' motor coaches. I also joined Woodalls Diamond Club (Free) because they have a big rig search category. Always, no matter, I use Google Earth to checkout entry and exit as well as the park insides.
BTW, RV Park Reviews is pretty good and some people do list if they are a big rig and have problems. I generally do not look at comments about bathrooms, amenities or neighbors
The biggest problem I have found for us is that at 13' 4" most parks do not think of height. The other problem is turning radius. A big rig to them is a 40' Class A.
With all the "big rigs" out there, many parks have added the classification to not lose out on the business, but they are actually not big rig friendly. For example, we had to be in northern Washington and only had one option. The KOA in Linden. There listing everywhere said big rig friendly and I even called them to describe our rig. Oh Yeah, no problem! It was a huge problem and we had to spend our few days there for business in the field at the back.
Believe it or not, KOA's are pretty good, but have gotten very expensive...especially for "super-sites." Very kid friendly.
West is better than east for finding monster rig friendly places. North of New York, there is a sign that flashes, "Don't Even Think About Camping North of Here!"
So, I do really recommend Best Bets for Big Rigs and Google Earth to be sure.
Sorry to say it, but when we see a campground promoting quiet country environment with shade trees, we go to Flying J
Bob