Magic Sculpt is the bomb! This stuff hardens like a rock and sands very nicely. Spent about 6 hours today sanding and detailing. Drilled out the holes for the rivets, which will be filled with ball bearings just past the half-way point. My best friends today were a set of three tiny jeweler's files. Looks like I'll need another pass of Magic Sculpt for tonight, try to finish up tomorrow and start the next mold. A few more comparison pictures up on Flickr.