Idk what everyone else's deal is... these are the best aftermarket barrels for glocks - Lone Wolf Arms AlphaWolf Threaded Barrel

This is my go-to threaded barrel for my Glocks. Works perfectly in the 19, any generation. I also use their Glock 43 threaded barrel in a 43X, and I have their Glock 42 threaded barrel in a 42. The barrel extends far enough for your booster piston or piston retainer to avoid hitting the recoil guide rod's end cap. Never had cycling issues or accuracy degradation. If you are looking to suppress a 43X, this is the barrel you want. For your 19, this is the best value threaded barrel on the entire market. Suppressing a 42 was fun but my suppressors are a little heavy for it.