I've got an OP/TECH strap for my Pro-S.

It's a great strap. Very comfortable.

Here's the thing regarding the fitting of the lugs. They fit well. Maybe a little TOO well. It's very hard (for me at least) to remove the lugs. So I don't. Even when I use the camera on a tripod. It's just too much of a hassle. But I have absolutely NO fear about the lugs coming loose.