I have, and still plan some of my rides using the parks as vias. There is a lot of good riding in between them. These routeable maps allow for a little cleaner planning. It is forbidden for you to ingress and egress except for the designated trail heads. But, many of the parks have trail heads on opposite ends allowing for them to be stitched together. So, you can treat them as a sand box. Or, you can use them as via to a destination. And, certainly pick up a map when you enter, they are very dynamic.