External safety is great for folks who don't pump thousands of rounds down range annually (i.e. the majority of the folks in the military).
I haven't seen what the Army describes as modularity, but S&W, and Glock (maybe others) offer different sized backstraps for pistols, so one size fits all shouldn't be the standard.
Give Soldiers $500 to bring the 9MM of choice? Who buys spare parts, where are those parts stored and how do you get those parts into theater? Logistics turns the tide of war.
Having a safety doesn't slow an average shooter down (thumbing the safety on my M&P became 2nd nature for me).
SERPA gained a reputation for being a "Dangerous holster", I never had a problem, but then I don't put my finger on the trigger until engaging/clearing.
Fewer SHARP classes and more weapons time might be beneficial.
For those who say it's no big deal because it's only a pistol. I disagree, and I submit this photo :
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