I would give it 4.5 stars it it was possible.  It doesn't keep me super warm but it does a good job and I like the style.  The material is rough.  A little rougher than denim.  I still felt a little cold in 40 degree F weather (I'm from southern California so 40 degrees is cold to me), but wasn't too cold.  The only thing I dislike about it is all the lint that sticks to it.  It sticks to it very easily.