The 10mm conversion barrel was a cost-effective way to shoot 10mm out of a Glock. It worked 99%. However, I did not want to wait for the barrel to "break-in" and didn't want to deal with different spring rates and/or extractors for it to be 100%. Solution, bought a Glock 20. Like my father used to tell me, better to cry once than cry all the time. BTW, Glock Doctor (Desert Scorpion) came through for me with a great price and super-fast shipping. Sorry Colorodo Glocker, I know you love your conversion barrel, but for me, it has to be PERFECT out of the box.