Originally Posted by
koolerb
Is there any disadvantage to using a mountain bike dérailleur? Any advantage to medium vs long cage in this model?
For this specific example, yes. The M675 is 10 speed Dyna-Sys, this is only compatible with other Dyna-Sys components. You would need to look for a 9 speed RD / non Dyna-Sys component,
If you are looking at a 32T max on the rear, then a Shimano GS road rear dérailleur will work, although you may need to reverse the B screw,