Somebody here (I don`t rememember who) posts occasional reports on how his touring Nexus is doing. Seems to me it had quite a few loaded miles, but I don`t know what kind of terrain. Try a site search on Nexus and you`ll probably find some of those posts By my understanding, the Srams are tougher than the Nexus ones. Also, I think BF uses Dualdrives on some of their tandems- again, I don`t know if that`s similar toughness to the iMotions.