Duran is so my favorite of the crop of romance writers who started publishing in the past five or so years. I tend to think of her, Sherry Thomas, Courtney Milan, and Janet Mullany as a set of similar writers, like the earlier set of Laura Kinsale, Judith Ivory/Judy Cuevas, and Patricia Gaffney: writers with distinctive prose styles and complex characterization, especially for the heroines. (There is an ongoing tendency to make romance heroines significantly less interesting than romance heroes. A lot of readers seem to like this. I don't.) Basically, I love Duran's prose, although the flavor of the characterization might appeal to people who like Sarah Monette's writing as well.
This one touches lightly on class issues -- nothing particularly revolutionary, but I liked the hero's surprised interest in the heroine's muscled arms. Yes, this is one of the things that is bad to contemporary tastes and good to current ones, but it reminded me a bit of the Cullwick/Munby romance. Oh, Victorian notions of perversity. So many issues.