*Both rounds were fired at 100 yards into milk jugs full of water, from a suppressed 16.1" DDM4. Both penetrated 3 jugs, and bounced off the far inside wall of the 4th.

Both projectiles expand to the cannelure, at 100 yards. It is my opinion that their expansion thresholds are very nearly identical. Their expanded diameters are statistically identical, as well. The difference is the length of the "shank" behind the mushroom, and aerodynamics/velocity/KE

Man, that is nasty. Makes me happy having GD in the go to magazines.

My impression as well.  Another guess is that it will hold onto energy well at range and perhaps expand the useful performance envelope somewhat.