We have had PA for about 5 years, and love it, particularly for overnight stays. They recently added an app for IPad, which is so much better than the bulky book.
Our last renewal was for 3 years, for less than $100 as I recall. Pays for itself in a couple of stays, and we probably do 2-3 dozen PA overnights in the course of a year.
Most campgrounds that take PA have seasonal, day of the week, length of stay, etc., restrictions. Still a great membership if you spend any significant amount of time on the road. Last night we stayed at a beautiful Ohio SP for $13.50, as they offer the PA discount Sun-Wed.
what's not to love?
We prefer NF, COE, or NP stays for our weekends and serious down time, but for all those one-night stays PA prices are terrific. Whether it is good for any individual likely depends most on the kind of travel/camping you do.
Our motto: Spend less, do more.