I agree with TandemGeek. I upgraded from a 20 year old Burley Duet, with 27" wheels and Suntour components. It made no sense to start replacing components. I sold it to a new tandem guy, who was very happy to have a competent entry level tandem for $500. I bought a mid '90's Santana for around twice that number. This is a much higher quality butted frame, that has 700c wheels and lends itself to more modern componentry. I've since upgraded the brakes, wheels, and much more than I origionally intended, but I have something that is essentially 5 or 6 year old technology (9 speed, etc). Most importantly, we have a tandem that fits my wife (stoker) and me perfectly. Our old bike, in order for my wife not to be too crowded, was a bit of a stretch for me up front. If you decide to go this route, be patient and don't settle for a frame that doesn't fit right. Santana is very helpful, in that they keep the dimensions of all of the bikes that they have built, and can share them with you if you provide the serial number. This was comforting, since we were dealing long distance. When comparing frame heights, be carefull that you are on the same page as the seller with regard to where the dimensions are taken (center or top of tubing or seat collar), as this can make a big difference. The older Cannondales, seem to have a greater size disparity from front to back. This kind of ruled one out for us.