u pack a spare mag on ur person, the locking thing is kinda of a mute point, nice to have work but not necessary. Had my PM9 never had this feature, I would never have given it a second thought, sometimes just another thing to go wrong when needed. Not alibing for a gun tha thas it and it doesn't work right either, just saying for me. it doesn'tmatter. I never carry a spare mag. If I cant do it in 7,,,, I am probalby done anyways.