Was pleasantly surprised with the rain jacket fitting with just a little extra room for additional layers and being stretchy.

Had to return it because it runs super extra small in te upper chest. I'm a cup B-C and ussually any jacket or jerseay in S in my perfect size. Not the case with this jacket, it wasn't even close to closing the zipper. The problem in having them in M would be too long in the arms and waist. It may be worth giving it a try. Although it might be perect for flatter chests!! Apart from the size problem -for me-, quality is incredible and it's probably an excellent raint and wind jacket :(