I'm still skeptical bout a metal shield.....it may weaken the joints.
I think if they can get the weight right than it will be fine but they should definitely tighten the joints up so that you can pose it and hold the shield up.
I had my Avengers Thor holding Mjolnir for quite a while, no problems. I'm sure the shield will be same weight or even lighter. True the shield is bigger, but it isn't thick like Mjolnir.