Im still trying to see the niche of where it fits in. I dont recall the specific lot or brand of ammo but I vividly recall seeing ballistic testing about 2003-2004 in calibrated gelatin and was completely underwhelmed. As unimpressive as it was, after pentrating a IIa vest is was even less impressive, an ice pick style wound regardless of FMJ or expanding ammo. I agree I would rather have any wound in the body over a bullet stopped on a vest but are there available stats on what percentage of shootings involve body armor in a civilian environment? If I was facing a known armored threat I would be reaching for more than a 5.7 or changing my aiming point to begin with. If the BG is aware/prepared enough to be wearing armor I would hedge my bets by selecting something heavy enough to punch a plate rather than hoping the BG is wearing soft body armor without an additional insert.

I recall the Sacramento Good Guy shooting and soft body armor was an issue. The entry team was already in place inside the building and the hostage negotiators provided the hostage takers with ballistic vest (which the BG tested by shooting with a 9mm). The team was advised of the issue and aiming points were adjusted. Aside from the timing of the sniper initiated assault the entry team did just fine with MP5's shooting 147 hydrashok.

If someone wanted to exam the Hollywood bank robbery you could make an arguement that a 5.7 might have penetrated enough to make a difference (mix of soft armor and plates) but the more appropriate solution for an average officer is still a full size 5.56.

Hunt hard, kill clean, waste nothing and offer no apologies.

"In rifle work, group size is of some interest...but it is well to remember that a rifleman does not shoot groups, he shoots shots." Jeff Cooper