I bought those locks to replace my old Hennessey locks. The hennesseys were to loud and the screw opened regularly. With those locks this can't happen. These locks are quiet and very robust. But: 1. The screws are big. On my Hagström Viking i had to drill a bigger hole into the metal tailpiece. 2. The normal holes in my strap are too small. You (or your local shoemaker) have to drill a bigger hole into the strap.
Summed up those locks are the best i had. Better than hennessey or Schaller. I recommend buying those locks! I'm happy with them even when the installation is a bit complex.
I'm sure I don't have to explain why straplocks are a good idea! But many of the designs are so bulky and awkward. Loxx are different - they're much lower profile than other brands, so the strap sits closer to the guitar (like if it was on a strap button). Installation is simple, although you only get one tool (not 2 as in the picture) and it's not very ergonomic, so tightening the screws is tricky. Once fitted, you never need to worry about your precious guitar nose-diving towards the stage again. Great, simple, affordable. 5/5.