If you browse around on youtube you can find some comparison videos of 9mm vs other calibers. The new 9mm ammo is much better than it used to be and compares well with .357sig, .40 and .45 auto. The game has changed a lot. With 9mm you get good performance and less recoil and more rounds in the mag.
Exactly right, 9mm has gotten way better over the last number of years, when I started carrying it was in .40, but switched to 9mm about 7 years ago.