I became a Registered Professional Engineer (Civil Engineer) in 1973 while working on the Metro subway project in Washington, D.C.  Although I moved out of the state in 1974, I have maintained my registration in Virginia.  Now that I am retired, I have been able to serve as a full-time volunteer for non-profit organizations on various construction projects.  It adds to my credibility as Project Manager on these projects to be a Professional Engineer.  Even though I believe in the concept of continuing education, I will let my registration lapse before paying for continuing education courses.  You should expect a significant drop in the number of registered professionals after you implement the mandatory continuing education requirements.