I have Schallers on most of my players (guitar & bass). I think someone mentioned that they don't have them on their Beatle bass, nor do I. Too light, and strap locks would be overkill.
For guitars that have the upper strap pin behind the neck, I use Marvel strap locks. The Marvel lock mechanism doesn't stick out as far as Schallers, which is a bit more comfortable in that area.
For guitars that have the upper strap pin behind the neck, I use Marvel strap locks. The Marvel lock mechanism doesn't stick out as far as Schallers, which is a bit more comfortable in that area.