Sorry. I'm a virgin when it comes to this stuff. I'm guessing the HK hook(??) Isnt the best choice. But I'm ignorant to how the QD it's attached.
It's definitely up there in my least favorite options.
Do you have a pistol or a carbine?
Where do you want the sling to attach to the gun?
The PMM QD's use a finely machined part that goes through the eyelet in the back and clamp on both sides. They then have a cup the QD head pushes into. These can be purchased for either side, and the confusing part is each can be mounted on either side as well, but it will change the angle the cup sits at slightly. (Allowing you to fine tune your preference very specifically)
If you were running a 2pt sling, they also make them for the front which replaces one of the factory chassis screws, and has a cup where you would expect a nut to be. This is located right behind the factory eyelets up front. These are not side dependent and you can simply put the QD cup on whichever you prefer.
This is vastly superior to using a jingly keychain ring through a plastic eyelet and then a hook. But to each their own.
The PMM mounts are painstakingly well machined and fit like red hot magic.
If you have never used a sling before in your life and are completely clueless go grab a belt, under your left arm, over your right shoulder and fasten it. Grab a short piece of cord and go through the eyelet of the gun on either side and tie it to the belt buckle securely. (Paracord, laundry cord would be a good idea.) Position the buckle to the center'ish of your chest. Once you're sure it will hold the weight of the gun. Drop the gun. (You will probably realize why 1pt slings suck in a few drops)
Now decide where you want the gun attached to the sling so it lays in the least offensive position. And buy that.