It is worth the membership. But if you are a full timer and thinking it will save you half your camping fees during the year you will be disappointed. It will pay for itself quickly, but then you may not be able to use it for another month at times.
When we travel we have certain destinations in mind as full timers. There are things we wants to see in each state. There are normally certain routes that take us to those places so therefore we camp along those routes. We first look for PA campgrounds in our targeted areas. But we are not going to add miles to a trip and spend extra diesel to save $20.00 for a night in a campground.