Our first tandem was a Cdale off of CL. Aluminum frame was really stiff. Even w thudbuster seatpost it was hard on the stoker. We are a 295# team, combined age 119. Cdale too big for stoker so we decided to upgrade and tried steel co-motion and steel daVinci. I actually liked the sync chain on the co-motion since it tied us together and I knew where the pedals were all the time. But, when stoker tired, I ended up pushing her feet around. For us, the daVinci ICS is great. Stoker can stand for butt break or for bumps, or just quit pedalling when she tires. I can just keep pedaling over bumps etc. Steel frame is a bit more forgiving. We have carbon fork, disc on back, w cantilever brake on front, thudbuster stoker seatpost. Works for us.