I use it regularly to choose the 30 or more campgrounds where we stay each year during three months of travel. I get a little uneasy when a place hasn't been reviewed in a year or two. The site is like Gas Buddy - it works when people participate.
Got burned recently on a campground with a lot of 10 reviews. It turned out to be a real dump, but not much else around and we just needed an overnight so we stayed. I went back and read the reviews and realized points mentioned were oddly consistent, written by people with just two or three reviews posted. Had to be the owners or their relatives. No one who actually travels by RV would consider it a 10.
But usually, RV Park Reviews works for me.
By the way...Someone mentioned recent issues with Tom Sawyer near Memphis. A few days ago, we left a message 24 hours ahead of our desired arrival. No call back. Emailed and called again next morning. Still no response. (So we skipped them and drove a couple more hours to a modest place where we stayed once before.) Must not have needed our business.