Let me start this response by stating that Glocks are well made firearms, relatively cheap and reasonably accurate. They make excellent duty weapons for a department that wants a simple to learn manual of arms and a short learning time. For a non-firearms knowledgeable trainee, the Glock is probably the easiest firearm to learn (DA revolvers evcepted)
That having been said, I don't carry a Glock. My experience with them is limited to the model 23 I purchased years ago when I decided to join the rush to become a "Glockster". First thing I noticed, no external safety, a negative for me as I sometimes carry Mexican style. 3.5 lb. trigger + no manual safety+ Mexican carry= possible loss of relatively important piece of anatomy. Conclusion, Glocks need holsters. Next I noticed that Glock grip angle is wrong for me. Rapid target acquisition from the holster was hindered by the tendency of the Glock to point high. Practice resulted in being able to compensate for the high point, but at the cost of time required to execute the shot. Before I get blasted let me say, if the Glock fits you, great, enjoy. Third and biggest gripe, aside from what has ben said as to the cheap plastic sights is that being a reloader, I can't see the value in owning a gun that will not safely shoot my lead reloads without frequent cleanings to prevent lead buildup and possible KB.
Negatives for me outweigh the positives. I still own the same model 23 complete with 3 hi-cap mags and on occasion I still shoot it in hopes that the faults I found would have magically disapeared. So far, no luck. Chances are the Glock will live out its remaining days in my safe with others that didn't make the cut.
For those who live and breathe Glocks, great, enjoy.
What do I carry? Either a DA Smith revolver or a Para LDA 45, sometimes sans holster sometimes with. Just my preference.
JPM