I have posted about the Novoflex option every time this crops up, so it may not be useful to post again. However...
The Novoflex comes with or without a "clamp" option. Without the clamp, it works like the speed gimbal and the speedilens.
I originally bought the basic option, but I found it inconvenient that I always needed to support the camera, and quickly added the base clamp. This works just as quickly and easily, and doubles up as a ball head on a tripod or monopod.
On a monopod, if I'm waiting for something to happen, or if I need two hands to make a camera settings change, I can simply lock the ball in place. For me, I have found this transformed the usability of the set up.
It's very pricey, at £275 for the full kit, and £70 for the basic ball and cup option.
Novoflex create premium, precision engineered, professional photography equipment including lens adapters, macro bellows, ball heads, tripods and more.
novoflex.co.uk