I bought these strap locks as I like that they are designed to that you can use them with a different strap if you forget yours, which is always a hassle with strap locks. The screw that comes with these Dunlops was both thicker and wider than the originals for my Ibanez RG and as I didn't have the proper tools to drill a bigger hole, I chose to let a professional install them. However, fitting the part that is attached to the strap was a breeze on my leather strap.
Another thing to note is that the strap will stick out 1-2cm more from the body due to its design, this is not something I worry about with my guitar but take this into account when considering this product.
Overall very happy with the quality of these Dunlops and I've gigged with them for several months now without any complaints and I'm sure they'll last me a good while.