It all goes back to the old Mozambique, and why, you would continue to shoot COM, if the first couple rounds had no discernible effect. And again, if youre reasonably close, why bother with COM at all?Chances are, you'd never know if he was wearing body armor in the first place. If you could tell just by looking, it would probably be too late.
Another question here too is, once you start talking vests, quick(er) incapacitation, and perhaps dealing with expanding distances, yet still being in the kill zone, are you still comfortable with the gun and accessories you choose to carry every day? How about your "true" skills and capabilities?