Traveling around the southwest I've been I've been asked fairly regularly about the length, type, and age of the RV when making reservations at private parks. While these vehicles have not been old enough to trigger the 10 year rule, I can say no one at any time has ever looked at the RV carefully or asked to see registration. In my stops I'm certain any RV which looked clean and well maintained would have passed the cursory inspection. Under the circumstances I could see no reason to advertise that it is 10+ years old.