Mendy. He is indeed healthy the last time I checked and Minny has let guys run on them before (see Ray Rice). Stewart is a guy I like but between he and Mendy I would go Mendy.
i don't think you can really go wrong with Mendenhall if he's healthy. He's all we got other than Mewelde Moore and they are not going to use him. Start Mendenhall.
The betting line went from 4-5.5. They know something. Pittsburgh might make a rout of this one. I don't think so, but Mendenhall could get yards if he's healthy. Maybe even a touchdown or two. I have seen nothing in the papers about any injury to him since that first mention 3 days ago.