i never had any tuning stability issues with the vintage tuners in my jazzmaster. i think people just hear "locking" and think they're like a locking nut or something. and if you have a locking nut, they'd be unnecessary anyway. but they are easier for quick string changes. thing that i don't understand is, who of us mortals are changing strings so much that it's a problem to use regular tuners? i can see that being useful in the heat of battle, where you only have one guitar, but most people where it's mission critical will just have a backup guitar. or if you're a big shot you have a tech, so i guess it makes it easier for them. or if you record a ton as a session guy and put new strings on every session. so i'm not really sure the point of them myself for the average person. they either seem like something that is unclear for the user, or the user likes to have "tactical gear" that probably won't get much use.