What is it you want to know? It shoots the same as a 45acp. For those that may not like the grip size of the 21, the 37 may be what you are looking for. The recoil is no different, accuracy is the same and so is the velocity for the most part, the gap does better with lighter bullets, while the acp does better with 230grs for speed. Only down side I've had yet is the availability of ammo at retailers, but if you reload that is no problem. You can use acp reloading dies. Not sure if Glock is still pushing lower prices on the distributors, when I got mine, it was $50 less then the rest of the line.