Nice but too small.
I'm giving this shirt 4 stars because it appears to be a well-made product. Can't really speak for the performance since I didn't keep it. I wish I had read the reviews before I ordered. This thing isn't just tight, it's SMALL! Very small in the shoulders, chest and arms. I'm 5'11" 185 lbs with a 34 inch waist and I ordered a Large. It was snug, but acceptable in the waist, but tight to the point of discomfort in the chest and under my arms. I tried to zip it up and thought I might asphyxiate.
Rather than mess with trying a size up, I'm just going back to a Smartwool Large which fits me perfectly.