This jersey is so comfortable. It fits tightly, and looks and feels great. I am five feet seven and weigh 120 pounds. I bought two medium, one in the dark blue, and the other is pink. I have used the earlier generation of Perfecto jerseys for the last two winters and didn't think anything could come out better than those products. I found the new versions block out the wind even better than my older versions. The jerseys keep you warm without holding in extra sweat. I stay fairly dry even after two hours on the bike. Living in Southern California, I don't usually feel the need to layer underneath. When I do, the jersey is almost too warm for my climate.

I was very excited to get this jersey based on the description. Sadly, I had to return it due to the odd fit. I am 5'8, 130lbs and typically wear a size 2 or Small. But Castelli does tend toward the Euro sizing and I have a short sleeved Castelli which is a Medium and fits well. I ordered a Medium and a Large in this to cover my bases since I assumed I would wear a base layer under it. The Medium was out of the question on fitting over my arms. It was so uncomfortable and dug into my armpits. I assumed the Large would be IT, but the arms didn't have much more room and still dug into my armpits, even though the sleeve length was longer. The rest of the Large body was then too roomy. Also, on both of these the neck was widely stretched when zipped up, probably tugging from the arms and didn't have the nice snug look of the pictures. One comment on the color...the pink is VERY bright. If you want to be seen, you will. Think blaze orange hunting gear. It's close to that. The pictures on-line make it look a bit more toned down and flattering. I have no idea how this performs as far as wind or water proof because the sizing was just too odd for me to take it for a test run. If your arms are very thin, this may work well.