Nickwrote a review of Castelli Perfetto Long-Sleeve Jersey - Men's on March 30, 2017
Familiarity: I've used it several times
Fit: Runs small
I am super impressed with this jersey, which seems basically the same as my long-sleeve Gabba. In temps from the high-30s into the 50s I am comfortable, which is an impressive range. It really is windproof yet still breathable, which is amazing because so many products that claim to do this really don't.
I got this in size large rather than medium like my Gabba, and the larger size is arguably better for colder weather. I am 5'10' 150 pounds, and the medium is almost too short in the front and sleeves, and it could not be any tighter or I would not be able to zip it. This one is longer and a bit roomier for a bigger baselayer, but both sizes work for me (I am almost always a medium though, for reference).
Along with its windproof qualities it is great at shedding water. These materials change my attitude about wet rides and allow you to go farther with more comfort in the rain. These are some of the best pieces of cycling gear that you can buy. The Nano Flex bib shorts make the perfect companion, since they are also very rain-worthy. But I really wish Castelli made shorts and/or tights from the Gabba material to pair with this jersey, as the Nano Flex is not windproof and not warm enough for me on its own in colder temps (like sub-40).