We have a Primera Co-motion tandem. We love the bike but where we ride the road tend to be very rough and I feel a lot of road buzz on my hands. I do have a carbon handlebar. My main reason for considering the Tandem Duo fork is if it will the ride smoother, especially when we go for 3 or 4 hour rides. This is our second tandem, the first being a Trek 1000 and overall I find the Co-motion a much nicer bike than the Trek. I do plan in the future to purchase one more tandem with a full carbon frame so I could use the Tandem Duo fork then. We have do have front and rear disk brakes which I really like when we do tours in the mountains. Any advise would help.
I have tried 3 different Carbon handlebars on my singles and found some do a better job of dampening road buzz. I guess some are designed only to reduce weight. The FSA K-Wing does a very good job of dampening road buzz but they are not the lightest carbon bars out there. They are usually 50g+ heavier than advertised.