Pros: Solid Shifting, Light Weight, Does Not care if the chaing is stressed or relaxed
Cons: Wass concerned about the Carbon cage, but it is still holding up GREAT
Recommendation: This set came on my Specialized Stumppy 29er and it has been flawless for well over a year. The shifts are incredibly PRecise, It doesn;t care if you are grinding up a hill or crusing down a flat twisty section, the gears just jump straight to what you call for. I have crashed several times into rocks and stumps etc.. I have bent my Hanger twice, and the derailure is still solid as it was when new. Coupled with the SX-9 shifters this set is great!
Pros: Durability--I put 5 years on this item, including 4 major accidents requiring derailler hanger replacement.
Smooth--shifts like a dream--always.
Worry free--rarely needed adjustment, no matter how badly I abused it.
Cons: I guess I could grouse about price, but this came with the kit I ordered on my bike, so I didn't think about the specific cost of this item.
Recommendation: When I finally beat this one beyond recovery, I wanted to replace it with exactly the same item. But my LBS only had an X9 in stock and, being impatient, I went ahead and got that. After I put a season on the X9, I'll decide if it was worth the downgrade.