I must be lucky in that I never had lock stick on a 21. Regulars, it’s almost the norm. On some classics also. My reason for not liking the 21 for many years is the reaction I got from people stating it was too pointy and I was carrying a machete in my pocket. These same individuals admired my regulars though....lol. When regulars dried up, I kinda had to go to the 21. I have many lifetimes worth, so I am good..... If I bought a 31, it would because they had an inlay or CGG/UG that I just had to have.