Originally Posted by alan s

Shiftmate has a range of products designed to do the essentially the same thing. The Tanpan is designed specifically for the newest generation XT and XTR derailleurs, one piece of housing is required, and the wheel is made of Delrin (thermoplastic). The Shiftmate 8, which is the comparable product, requires two lengths of housing, the wheel is metal, and the unit is inline with the cable housing, rather than inserted onto the RD. So in theory, at least, the Tanpan should be a better product. In doing a bit of research to solve the problem of wanting lower gears, there is not much out there in terms of reviews or options.