After market mags are about the only way to get a Glock to jam.
If you are buying high caps for a 23, I suggest buying one 13 rounder and the rest G22 15 rounders. They fit in the G23 but stick out a little. Carry with the flush fit 13 rounder, carry the 15 rounders as reloads. When you need to reload, you won't mind the little bit of hang at the bottom, but you may appreciate being able to go bang a few more times.
If you do buy pre-bans (cause the follwing is all illegal with post bans) don't mess with +2 extenders. The Scherer ones pop off and dump ammo. The GLOCK ones are hard to get. Both require longer springs to work well. The +4 or +5 140 mm extenders from several vendors, Taylor Freelance, Arredonda, Glockmeister, etc, work very well, however.