I carried a M9 on my deployments. It's not my favorite pistol, but I don't hate it, the main problem with it is the terrible magazines the Army buys. If you had good mags and the recoil spring wasn't 20 years old, it generally worked fine.
Iraq and Afghanistan had a lot of situations where having a sidearm helped. Going into meetings with local police or sheikhs or whatever, sometimes a rifle wasn't feasible and it was nice to have a sidearm because we didn't trust anyone. I know of one pistol kill when a guy got jumped on base by a local interpreter. There is more to combat now than infantry on patrol.
The Army as an institution still needs pistols. The questions about which one and how much are still valid.
The current pistol is fine considering the manpower cutbacks. Money for more troops vs. A new pistol.......I'll take more troops.