Light, non-itchy, but still cozy-warm!  I live in Alaska.  While it's not quite the igloo-dense ice age that some picture up here, there's still plenty of winter and days hovering around zero.  So, we're big fans of wool up here, and Icebreaker stuff is some of the best to be had.  If these were a little more affordable, I would have gotten one in every color!  As my budget does not allow for that, I plan to get a few every winter until I have a good selection of them in my closet.  Unless I become a millionaire.  Then, I am buying every available color and model.

Note, I have a large bust but small rib cage: 32E (36 inches around the bust).  The size small fits me just fine.