Well, when I first bought my guitar, Epi Les Paul Standard, I thought I better protect my purchase with strap locks. The store I go to doesn't stock Schallers (I think that's how you spell it) , So I got some Marvel ones (Which the guy threw in for free). It's been a while and they have been working well, UNTIL NOW! I was at home hosting a Minecraft LAN server with my friends and a song came on that I new how to play. So I took her off the wall hanger (Hercules, works great) and starting playing, to my astonishment half-way through, the front lock popped off (The one closest to the fretboard, IDK) and the guitar fell forwards pickup side down, onto the ground. At first I noticed some minor chips in the binding around the jack area. Also I noticed each string had dropped down a slot in the nut (strange, yes this left the high e with no slot). Then feeling the neck I felt a crack close to the headstock, I thought this was the laquer but the headstock has snapped. It's being held in place by the tension of the strings. The nut has also moved from the original position, exposing the natural wood. So yeah. Also, I believe installed them correctly, as they've worked for like 3 months. Edit: The crack is quite large, goes from the nut area around to 3rd/4th fret.