It depends upon what you plan to do with it.
If you're going to just shoot it, or open carry it, I'd recommend the Glock 22 (I have one). When I tried carrying it concealed OWB, no matter what I did, it seemed to stick out of the bottom of whatever sweat shirt of sweater I wore. I can ONLY carry it IWB.
If you're going to carry it concealed, I'd recommend the Glock 19 or Glock 23.
My Glock 22 has quite a bit of muzzle whip with certain loads. When I was looking for larger capacity CCW auto, I had to choose between 2nd Gen Glock 19s and 23s from Summit. Based on my experience with the Glock 22, I picked a Glock 19, with which I've been very happy. If I had it to do again, I'd have gotten a Glock 23. Since I got my Glock 19, I've learned that it's quite popular to buy Glock 22s/23s and buy an extra 9x19mm barrel for them. When a friend was making the same choice, I advised him to go with the Glock 23 and an extra barrel. He's been extremely happy with it.