I love love Patagonia gear, I've been buying their apparel since the early 90's & 9 times out of 10 I find their sizing for me be generally to be between a large and a medium depending on the cut of the garment, unfortunately with the nano air hoody I just can't get an available size that fits me, the fit is slim and tailored but after trying the large and and the XL niether size fits me, the body fit of the XL is good if not a litttle on the large size but the arm length is way too long, the large however in the body fit is more like a medium and is too small, the fabric and performance of this item from Patagonia I'm sure in use will be as good as any of their gear unfortunately I find the sizing of this piece a bit hit and miss and for this reason would recommend if at all possible to try the jacket on for size before purchasing
This review was written in the old system and had content requirements that are different than reviews written today.