I want to make a 3D arm mold - of a hand up to the elbow. So, I was thinking of doing it using molding chocolate and PVC/wire and then wrapping it in fondant....but has anyone tried Rice Krispie treats? I think it might work better - well easier anwyay and then I can wrap that in fondant or white chocolate (colored of course with food coloring) dough....just looking for some thoughts.

I'd probably do RKT. They are cheap and easy. The only thing you have to be careful of is the finished surface. You have to make sure you smooth out the dimples the krispies leave before you cover it in fondant.