I decided to replace my Wimberley version II gimbal clamp with the Really Right Stuff PG-CC cradle clamp as I have always adored the lever action from their quick release clamps. It is much simpler and quicker (in my opinion) to pop open the release, slap the plate in and close the release. I do not think there is anything wrong with the Wimberley set-up, it just has become a little pain to screw and unscrew the small diameter knob.
Here is a quick view of the set-up:
The above pictures were taken at a local marsh and the quick flip of the lever let me get set up a lot quicker and sometimes just a few seconds is the difference between getting a shot and not.
My Take: Overall, there is not really any weight savings as they are very comparable in weight. I like that the lever is more compact than the screw knob, which makes it easier to fit a lenscoat pouch over the set-up. The fit and finish of the RRS cradle clamp is perfect. Machined and anodized to perfection. Definitely worth the money. The set-up shown above is a Nikon 600mm f/4 G VR lens with the Really Right Stuff LCF-13 replacement foot, Nikon D3s on a Gitzo GT5541LS tripod and of course, the Wimberley Version II gimbal head.