I wanted to just chime in too Matt, and say you did a really nice job sculpting that. I'm not a very savy sculptor but you've got some real talent. I imagine your profession's helped you learn casting well too.
A buddy of mine makes prosthetics and he learned that way... I just picked it up along the way in customizing to where I made a pretty professional set-up in my shop to make mine, but it's got so much dust on it I'd have to start an archeological dig to find it I think.
Really though, just wanted to say how nice the final product turned out... Really sharp man.