Jaime Sirchio wrote a review of Patagonia Nano Puff Vest - Men's on October 8, 2011
Great vest, Im 5'8'' and 165 lbs and the medium fits perfect. I wear it over tbe patagonia R-1 shirt and it's a toasty warm combination. It's not bulky at all and packs down really small. once you put it on you can really feel the heat it generates.