I wisely ordered an L and an XL to make sure I had one that fit. The return process was super simple. I spoke to a number of individuals with no hold time and each was remarkably pleasant.
I needed the XL although usually I fit in a L. The jacket is nice and warm. I was apprehensive of the vents in the front, but even with a backpack on, I have good access and plenty of ventilation. I would say they cool me off better than pit zips because they are are not covered by my arms. I can really feel the airflow when I am cursing. Only thing I would add is a pocket on my sleeve for my ski pass. Everything else is solid.