Good post and thanks!
Some might ask why a penetration depth of 16" might matter. It varies from person to person, but take a tape measure and measure from the outside of the right arm over to the location of your heart. For me that distance is 15". One never knows how the target will be presented, so a shot from the right side of the threat could be possible and maximum penetration would be very desirable.
At least that's my opinion.....