I used to use those; they worked fine and were perfectly secure but I found they do slightly change the feel of how the guitar hangs as it's a relatively loose metal on metal connection, so the guitar kind of swings on the axel (which you can also hear if you're playing not plugged in).
I prefer normal strap pins with those cheap rubber washer type strap locks on top, but I don't remove the strap when playing sat down.
Edit - though on second look they seem to be new "silent" ones, so maybe they're better. My old ones rattled quite a lot.
I used to use those; they worked fine and were perfectly secure but I found they do slightly change the feel of how the guitar hangs as it's a relatively loose metal on metal connection, so the guitar kind of swings on the axel (which you can also hear if you're playing not plugged in).
I prefer normal strap pins with those cheap rubber washer type strap locks on top, but I don't remove the strap when playing sat down.
Edit - though on second look they seem to be new "silent" ones, so maybe they're better. My old ones rattled quite a lot.