Depending on the unit, many SO get to choose their personal weapon (read as pistol). I knew several guys (last couple I knew have since retired) that got to pick their when they were with the teams. Recon never did get a choice, but they carried M9’s at that time as did the FAST Teams. Many MSG had to carry 1911’s though. It just depends on command.
The Beretta has served our military well for many, many years. Biggest problem with them now is that they are all worn out and need replaced. Last time I qualified with mine was too long ago to admit, but shaking it made it sound like a maraca. We entertained ourselves in the field by treating them as such… Just saying.