Does anyone of you do this exercise?
It allows for full rom in the scapula, conditioning the serratus anterior and supoposedly builds tremendous punching power.
Only concern I have is whether a lot of the body weight is resting on the back of the head and in how far this could potentially be dangerous in the long run.
You should only bridge to shoulders. Bridging to neck or crown pretty much always trashes your neck in the long run. You'll get more people off you if you bridge high since this gives you more possibilities for movement, then cervical issues will plague you from the time you are 30-ish. Totally not worth it (seen enough guys who really wish their coach hadn't made them do high bridges in HS or college).
I can see the merits of this exercise. Since pros don't have more weight than gloves on (16 oz. is tops and you only wear those if you are a sissy) the bells are for core training.
So, I'd say that if you are a fighter with core stabilization issues, this could be a pretty good way to fix that. The abs have to brace, the glutes have to keep the hip in alignment (bane of grapplers) and all the while a single limb is in motion. I doubt that it is a primary exercise, so, doing these every day probably won't really make much of a difference after a couple of weeks. I'd say drop one of the bells if you really want to counter torque, but that's me.
Said more plainly, this is probably a corrective exercise. If you need it, give it a shot.