New Military Handgun?
Whatever they might select, I hope it has a slimmer grip and a shorter reach from the backstrap to the face of the trigger than the M9 does.
I have big hands & long fingers and I personally really like the Beretta M9 but grip circumference and reach to the trigger are WAY too big for many people. I found this to be a big problem when teaching basic marksmanship when I was a CATM specialist in the ANG. The damn gun is simply too big.
Apparently the S&W 99 is under consideration. I have never fired the DAO version of the S&W 99. I have about 200 rounds through a .40 cal DA/SA S&W 99 that a local PD had as a test and eval gun. The gun was very comfortable in my hand but I thought the trigger pull was very stiff and stacked funny toward the end of the trigger travel. (This impression based on only one range session with the weapon, however).
I always thought the M1911A1 with the arched mainspring housing, or the S&W 39 had a particularly comfortable grip that fit shooters of many different hand sizes.
I hope whatever they select has an all steel or polymer frame. If you shoot an alloy framed gun enough, it'll break. (Usually about 30,000 rounds)
Any military handgun that has to fire FMJ ammunition will have questionable stopping power due to over-penetration. Doesn't matter if it's a 9mm or a .40 or a .45 or whatever. Bigger diameter is probably better. Maybe a bullet of 165 to 200 grains in .40 or .45?
I can't believe this is a real high priority for the military because very few soldiers carry a pistol as a primary weapon, other than the military police of the various services performing the law enforcement mission on base.
People who were never in the military have to remember that the "average" GI
gets two to eight hours of training on the handgun, fires some simple qualification course, and THAT'S IT! They usually expend about 100 rounds or LESS and that's the extent of their training. MPs and SPs usually qualify twice a year. Pilots qualify ONCE IN A LIFETIME unless deploying to a combat zone. So, you can talk all about cocked & locked SA handguns in major calibers all you want, but you have to remember that the operators generally don't have any real training.
MPs assigned to an SRT or SPs assigned to an EST usually train more than that, as do the various operators in the special warfare community, but they are the exception and NOT the rule.