Personally, I don't think the dex will help that much with the unwanted hair growth....if it's only the hair growth that needs to be treated with the dex, then Vaniqua cream would be the better route I would assume, as long as the elevated androgens don't cause any other worrying symptoms.
I have taken Dex and i had side effects from it at a dose of 0.125 mg, which is the lowest you can take. Some people do respond well to Dex without any side effects and other like me don't:(. I had some weird breast/chest pain going on a well as fluid retention. It all went away once i stopped dex. Now I am taking prednisone, which i so far have no problems with.
But don't let my experience with it frighten you. Again, everyone responds differently to it. So far, i have had no weight gain from dex nor from prednisone.....so far;)