This is just what I was looking for in a very light jacket to throw on when it's cool out and I don't want to layer - considerably lighter and thinner than the Micro Ratio. I almost always wear a Large but the M in this is a nice fitted look and will make a great mid layer with a shell over it. I'm 6'2" 175lbs with slightly longer than average arms and it feels good for Med.
NOTE:: The Amphibian color is about 3 shades lighter than it appears here, I was bummed at first but it grew on me pretty quick.
This review was written in the old system and had content requirements that are different than reviews written today.