You cannot leave the zipper open. There is a hard piece in the back of the zipper, it does not look good to leave it open. If you plan to close the zipper all the way up, it looks pretty good. Otherwise, it does not look good.
I purchased this item for my daughter who is petit and slender. The quality, size and construction were just right for her. She finds it gives warmth without excessive bulk. Very pleased with the item.
I love the looks and feel of the jacket. the only thing I am not crazy about is the inside where it zips. the inside flap is really stiff up by my chin. I am hoping that it will soften with wear.