I can't recall when I started using them, but it's been at least 5 years. Possibly more. It's on almost every Glock I own and several have a couple thousand rounds through them with zero issues. In fact, I've seen the pin on the OEM beaver tail walk but not the GFA pin. Except for the baby Glocks (26, 27, 43) I get slide bite unless I use the GFA or the factory beaver tail. I prefer he GFA because is fills in the recurved area of the grip and helps it point more like a Sig/1911/etc for me.
I also have an RTF2 gun (bought the frame and put a 34 upper on it) I use for matches. It's had a GFA the entire time.
Before you suggest that licensing, background checks, or other restrictions for the 2nd Amendment are reasonable... Apply those same ideas to the 1st and 4th Amendments. Then tell me how reasonable they are.
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