For $36 this is a decent and attractive wind vest but the MSRP is surely a joke, as is Castelli's inconsistent sizing. The material is windproof but cheap and you should be under no illusions that it is breathable - after a hard ride you will build up plenty of sweat inside. Based on my experience with Castelli jerseys I ordered a L (I am 6' but very skinny around the chest) and the vest came up far longer and wider than expected. As usual Castelli have used a cheap and unreliable zip, too. That said, it does keep the wind off, looks good, and adds versatility to your existing cycling clothes.