If your a vet DJ you'll no doubt have one of these (or something similar...there are other models out there) because you understandt the importance of getting the little things with the rig just right so you can concentrate on the floor.
I have two, one for the mobile rig ang tuther for home studio. What I like with the Gravity model is it's design and robustness. When in a rush the phones can be slung on the bracket without having to 'aim'. The clamp is sure and firm regardless of the thickness of the surface. Love the cable 'tidy' slots when the phones are unplugged.
There is a nut that can be loosened and the bracket adjusted to fit vertical surfaces (e.g. mic or speaker stand). Not sure how useful that is to most rigs. But when I tried it the bracket tended to slip off. So if that's your requirement look elsewhere, but for horizontal clamping this bracket is the tops.