I'm fortunate enough to be in a program that allows me to test Gore products (Gore MountainTech). I do not get paid for this but i do get to keep most products. That being said, i have a lot of jackets (including 4 Arcteryx). And the Beta AR is the one i use the most. The rest aren't even close...
The first thing you are going to notice when you put this jacket on is the weight, as in, where is it? Its very light in construction and has held up to countless hours in the backcountry, including some amazing cartwheels;o). After a full season and a few washes, it still looks brand new. I love how roomy it is, allowing me to easily layer up depending on the conditions and not sport the Michelin man effect. In the Back country i usually only wear a light or mid weight thermal underneath, on the lift, i'd wear a heavy thermal and my down vest. Front pockets are ample enough to store your skins, The hood fits comfortably over a helmet and can be adjusted down to fit on a head. The GoreTex is going to keep the wind and water out, and the Arc'teryx style will keep you looking good on and off the mountain. I even like to wear this jacket walking to the grocery store (which is often, it rains a lot here in Portland)
I'm 6'4 180 and the xl is the fit for me.
If you are thinking of getting this jacket, i have to say go for it. You won't be disappointed