The glock is a great utility gun, very reliable, but that's about it. It's not my favorite but it is my favorite carry gun. G19.
The Sig P226 and a 1911 are my favorites. Although any pistol is only good for fighting your way to your rifle.
A lot of people argue about stopping power vs. Caliber. But this is a fact, hit the subject in the pelvic area and they will go down. It may not stop the threat but a follow up shot on a non moving threat is easier. The pelvic region is highly vascular and a 400ft/lb shock to it will plant a man allowing you to get cover and shoot from cover if need be.
Also too small a handgun for a person's hand is not good. Under stress a person will suffer from loss of fine motor control, visual, and auditory distress so having a gun that fits the hand well is much more important than caliber, which makes the pelvic shot easier than attempting a head shot or hoping a center mass shot doesn't over penetrate. Training and I don't mean going to the range and shooting is very important so have a gun that fits. Good high stress training will help a person recognize the onset of the above symptoms and that's more than half the battle won in controlling those symptoms.