Overall, a good jacket. I'm 5.8, 150, the medium is fine, jut a little oversize, but perfect to fit a couple of layers underneath. It is light, wind proof and water resistant, wore it with one base layer and a sweater on a really cold day in the mountains ( single digits). This was rather surprising, bacuse it's not insulated. You'll have to be moving around pretty intensely, however, it's not made for standing around for too long.
Also OK to wear as a regular jacket/windbraker in the city, since it's pretty neat and low profile.
One problem though: the inside pocket ripped up, right across the stitch. I had my car keys in it and thought I'd lost them. This is not good, especially from Mammut! I've had cheaper, no name jackets that held up forever! I ended up finding the keys in a side pocket, where they fell into, through the hole in the stitch (these two pockets were only separated by that one line of stitch that tore up) so the two pockets are now one..
To sum up, it's nice and stylish, and the material is top quality.. but what's up with that stitching job, Mammut??