For me and skiing, it's a nice complement to the R-1, which i use on warmer days (both on top of merino base layer). For lift access skiing with the occasional inbounds hike, the nano-air seems like a great layer under a shell for weather from 10-30 degrees. Sleeves are a little long even though the torso fits perfectly.
This review was written in the old system and had content requirements that are different than reviews written today.