"Smartwool does it again. Warm & Form Fitting"
I am roughly 5'9-1/2" around 170lbs, with a bit of a beer keg. I have the large version of this half zip and I couldn't ask for a better fit. It fits well, goes under as a great base layer, keeps me warm even the freezing weather. It wicks away dampness wonderfully. It doesn't stink even after days of wearing it and sweating in it. I couldn't ask for more out of a baselayer piece of clothing.