- Familiarity: I've put it through the wringer
- Fit: True to size
- Size Bought: 100
I swapped out an S-works SL stem for this one for sizing purposes with the intention of swapping back for an S-works once I had my fit all worked out. To my surprise the Zipp Service Course SL is awesome! It actually felt noticeably stiffer than than the S-works, I think due to the square shaped cross section, and is lighter by a few grams. The finish is also much nicer. Needless to say I am staying with the Zipp. I highly recommend this stem. Uses T25 bolts so make sure you have the right tool.