I love the Sling-a-ling.
As a 3D target shooter, I spent a lot of time walking and waiting for my group to shoot. The shoulder sling allows me to carry my bow comfortably, and the magnets keep it out of the way while shooting.
The whole setup is extremely lightweight and doesn't affect my aim at all.
I'm one of those people who enjoy color coordinated gear, and the crazy number of color options for the Sling-a-ling allowed me to add even more of my favorite color to my kit.
I'd recommend the Sling-a-ling set to everyone who is shooting in the field.