Ok Im 5'10, 150, 39-40 inch chest, so any size recommendations would be greatly appreciated??...also, Im thinking of taking this backpacking with me to Asia, will this sustain a downpour for at least 10 minutes or so, and is the material pretty tough? than you

I think Arcteryx is hard to know in sizing... Seems much of the clothes are bulky in the torso for my liking. I have many products because I like the quality, quality is the same with Norrøna, but they are not bulky at all. To answer somewhat I am the same size as you, wear Small in Alpha SV jacket(no problem layering), Small in Beta AR pant, Small in Covert cardigan, but medium in Venta vest and squamish hoody. These clothes are worn in alpine environment in Norway (also hunting), I use medium in running clothes from Arcteryx. So in conclusion I would wait for more answers from others before ordering, that is if you as me, do NOT like bulky clothing. Regards from Norway

First, fit: You should fit well into a medium in most Arc'teryx gear. I'm your height, but a bit heavier, and I'm right at the top end of medium. The sleeves and body length are perfect. This jacket will probably soak through in a downpour. It's designed to be more wind-resistant and warm in cool conditions. Although the DWR lets it shed moisture, I wouldn't take mine out in the rain. Finally, it will take some effort to tear or wear out this fabric. It's pretty tough stuff.