These are too soft and too large, which causes them to fail when you need them most. You can pull the strap right off with moderate force, which will not save your guitar if you go to play and your strap is twisted or if the strap is at an extreme angle. After using these for a while, I noticed that the soft material causes them to turn concave, which doesn't look nice and makes it easier for the strap to slip off. I suppose it's better than nothing, but I would still handle the guitar carefully, which defeats the purpose of straplocks for me.
If HB is listening, maybe try again with a harder material and decrease the outer diameter slightly.