We joined PPA about 3 years ago and have signed on each year since. We travel a great deal, often staying on military installations. However, there are some stops we make with family and friends where military installations are not convenient. In these locations, we look first for PPA. Our experience has been good but you must pay attention. As with any park; we lay out the route, look for places to stay, look at PPA, look at RV Park Reviews then decide. Part of the issue with PPA are limitations on availability. You can find that on their website under the Notes section (
Passport America Campgrounds). We have always more than paid for the annual fee.
One further note, some of the parks are what we'd call "sketchy". Thus checking on reviews on RV Park Reviews.