Not 100%, not ready for edc - Shield Arms S15 Gen 3 Combo Glock 43X/48 15 Round 9mm Luger Pistol Magazine

Ran 125 rounds of 124 gr. brass cased 9x19 on my brand new Glock 48 MOS with Glock mags only, 0 issues whatsoever. Bought these Shield Arms mags along with the steel mag catch and ran 193 rounds, had 5 failures to feed which required a smack to the back of the slide to get the round into battery. Compression cycled all 3 mags 10 times each and fired 87 more rounds and had 3 failures to feed which required a slide smack. I don't know what exactly is causing the failures to feed/sluggish slide movement but it's not my job to diagnose someone else's product so I'm switching back to the original Glock mags and returning the Shield Arms mags. 10 rounds of certainty is better than an 15 rounds of uncertainty.