Unfortunately, most of them have loose shoulders joints. I'm not sure why this is but I'm guessing the torso pieces don't hold the arm in tight enough.
All of them have poor fitting waist and torso joints. The Shadows like to lean when they stand. Maybe the o-ring is too small?
In addition, the foot hole is too small for the given clear stands and the hands are very soft plastic. The right hand has a very small thumb and doesn't hold things that well.
Im quite surprised to hear that, I know these convention sets were expensive, so if I had purchased them I would be well pissed off !