DvlDog, in the USAF, the only people who get the M11 as standard are OSI (our equivalant of NIS). As most of our high ranking commanders are pilots anyway, they all get the M9. Even the PJ's and Combat Control guys I know get the M9. Originally, the Sig was supposed to be for women and others with smaller frames, but it just didn't happen that way. During the Gulf war there was a severe shortage of M9's. And rather than go with the S&W revolvers that were left, my cousin's squadron (F4 pilots) were permitted to bring their personal guns. He told me that almost everyone bought Glock 17s. I also know that when I was in Germany, all of the contract security guys used CZ75's but that is about the extent of handguns I have personal knowlege about.
edited cuz' I can't spell.