This is a nice jacket except for the odd fit. I have a lot of Castelli jerseys and medium always fits me well, except with this one. Medium was too tight on the shoulders and arms. I switched to a large, which is a bit too large in the torso, so I have a compromise fit. The jacket works well in moderately cool weather and I don't expect it to work as a full rain jacket, but it performs well in light rain for a limited time.
I have loyally ridden Gatorskin clinchers for many previous years and been happy with them. However, I just switched back to tubulars, tried this one, and it was a total loser. After 1000mi, I had a 2-inch patch worn through the middle core layer, and the wear layer was gone over the rest of the tire's center. Never again. Need to find a new favorite brand.