The Wife and Stoker loves the Thudbuster short travel seat post by Cane Creek, started using them several years back now. We have one on our Co Motion tandem and our Da Vinci Joint Venture 700 tandem. She says it really takes the edge off the bumps plus the Thudbuster does not knock your knee geometry out of whack as it works. We also use the Tandem talk wireless headsets they work well and keep communications clear and crisp.
Take Care All,
Bill G