The reviews are Right! Note style/sizing.
What the other reviews have said is true. This jacket is super warm (comfortably walked around outside with a light wool sweater underneath in near 0 F weather), super light, and super compressible (I easily stuff it into my bookbag). This has quickly become my go to jacket for the cold upstate NY weather. I even sometimes throw it on in the morning as the house warms up.
A note about the style/sizing. I'm almost 5'11", 38" suit size, 31" pant inseam. Given those measurement I thought I'd be a small, but it was too small. I ended up buying a medium. Also this is a *jacket*; it ends a couple inches below your waist. This isn't like my other winter coat which covers my butt. This jacket covers about half my butt and ends at about the pockets of my pants in front. I'm guessing the fit is due to the fact that the jacket is made as an ultralight backpacking jacket (need range of motion in the legs).