I like the skintones you achieved. And their personalities really come through with the way you've captured their different facial expressions. I'm giving you an 8, because I don't think the pic does your work justice. Great job!
From this distance they look very nice, but soem close-ups would help alot.
By the looks of it, the shield-logo could use some more highlighting, but it is hard to tell.
And on a more personal note: I would prefer NMM on the armour and weapons, but you have done quite well with the metallics.