So I've had this for a week. Was worried it would be too warm (50s) to trial. Wrong. A bit of a cold snap in the central US. But even the 50s this is right on target. Gets too warm, unzip. Easy. But zipped up and it will toast you right up. I have gotten 5 compliments from strangers. It has style.Product: I am 6' 200 lbs. 44-45 chest. Size Large. Sleeves and torso circumference/length are on point. Not much room to layer anything under it. It could be a layer itself, but I would think that should be left to sub zero temps. the weight is heavy. So it's no wool or polar fleece. Not easily packed due to bulk. The white has a slight blue tint to it. So don't expect pure white.My reason for 4 stars: the seam were the shoulder and sleeve join stand up. Like a football jersey without pads. This is probably due to the thick seams because of the thick material. Wondering if they will relax after use/wash.Overall I am liking this bad boy.Spyder makes amazing core sweaters/jackets. Its fairly lightweight for the amount of warmth it provides. I wear these as fall and spring jackets, and layer this under a jacket in the dead cold of winter. Easily washes and looks great. My second spyder paramount jacket (had to size up).I used to use heavyweight waffle lined hoodies under my winter jackets, but they can get too hot and are hard to wash. Spyder Paramount "sweaters" are lightweight yet warm, easily washed, and allow full range of motion.pros: zippered pockets, washable and keeps its shape, the arms can be pushed up and does not stretch out.Of the zillions of permutations that Spyder makes of their core sweaters. this is by far the most tailored. It's worth the extra... the waterproof zippers are a part of that extra... they match the jacket's. It's a bit longer than most of their sweater/jackets. 2 inches maybe. So covers you better. plus it makes the silhouette a lot sleeker.Outstanding as usual for Spyder. Not 3L so not windproof, but truly the top of the line otherwise.it's spyder, what do u expect