I am having a little problem with my shield mags only in my G48: Let me start out by as saying that my G43X & G48 worked flawless in stock configuration. I shout about 500 rounds through each without any problems. Then came the infamous S15 Mags that everyone says is 100% reliable.......... I bought fifteen sheild mags and two of the shield mag release catch's(steel upgrade) to go along with it. One for my G43X and one for my G48. My G43x ran flawless with the shield mags, 300 rounds no issue. My G48 on the other hand has problems. I keep getting random stoppages on different mags. I will reload the mag and it will work fine, but I will have another issue on a mag that worked good. So its completely random at this point what mag will cause a fee issue. I do have the upgraded mag release installed that shield arms sells on both guns. I have experienced this malfunction 11 times within 550 rounds through the G48. It hapend three times today as I was ready to yeet the Glock at the target, no joke- I was pissed. I and not an expert on this, I own a lot of Glocks and I have never had this issue before. From the picture with the circle on it. The bar on the bottom of the slide looks to jam the rim of the casing the slide to seize. My best guess........... I will also note that when I disassemble the gun, the guide rod practically falls out. I called Glock and they said it's normal, "It's suppose to do that". I never had a Glock where the recoil spring can fall out with the slightest touch or tipping the slide at the right angle.