I love my Sidi Dominators! They are comfortable to walk in (I just did a 2 week cycle tour in France), and are stiff and not clunky like some of the other MTB shoes. They are on the narrow side and I took a 38.5 instead of a 38. I wear a women's 6 1/2 and do not have narrow feet.
I think men and women's shoes are cut differently. Women's shoes tend to have a narrower heal than men's. The Sidis are expensive but from what I understand, do last a while.