Armpit Vents are Underrated
The pit zips make this piece perfect for layering. When traveling in the windy and cold conditions in Iceland, I noticed many hikers was dressed the same as I was—torrentshell on the outside with a light puffer jacket inside. Keeping the pit zips open helped let out moisture to keep warm and dry. This jacket does need nikiwax to stay waterproofed. I made the mistake of skipping this part of maintenance, and found the jacket does get wet in heavy rain. However, it just feels damp inside (i.e. the water doesn't soak through, but the material does hold onto the weight and coolness of the water).