I think they're neat but I want to be able to use Avid SD Ultimate levers with my BB7 disc brakes instead of having to use Shimano's levers... Do they make an XTR shifter-only? I know the XT set comes as a separate shifter if you so choose. At any rate, basically what I want is something that's not going to require constant tune-ups (I understand the occasional tune up due to cable stretch or smashing it into something), shifts smoothly, has a fairly light action in the shifters, and can take a decent amount of abuse.