Best built mag i've found - Mec-Gar Glock 17, 9mm Luger, 18 Round Flush Fit Pistol Magazine

This is the best built mag I've ever found honestly they are fantastic. The formed mag lock is smooth and does not wear the factory mag release in my PSA Dagger. The formed fluted sides ensure the mag dos not swell when loaded to capacity, which is 18, by the way. With 1 chambered you can carry with 19 rounds. Because the mags don't swell they load and unload easily with no need to manually strip the mag. I have approximately 150 rounds through each of the 5 mags I purchased and have had no issues.

These are well worth the price.