(Well, actually, I've yet to make a Winry costume (and when I do it'll be Sloth!Winry from the Recasted! series, but I digress..))
Anyway, a friend of mine decided to be Edward for our upcoming anime convention, Anime North, and due to my success with a thermoplastic called Wonderflex, I made her a full automail arm. It still needs to be tweaked (I'm remaking the grill to be smaller and smoother, and not cut off her blood circulation for example) but overall I love how it turned out. She had fair mobility, and because it wasn't shiny metal, it photographed nicely too. ^^
So here's the photo proof!