I've been meaning to share some shots from my 5D MKIII running ML RAW. Our viz has been really bad until recently and there are still a lot of particulates in the water.
In any case, I wanted to illustrate what I consider to be an amazing benefit from this firmware aside from the increased detail and latitude. I have a 8-15mm f/4L fish-eye behind a Zen DP-100 mini-dome. It has a fantastic MFD. With the crop feature on the firmware, I can get a 3X zoom factor on the lens. At the push of a button, I now have a 24-45mm lens with no loss of quality. Here is a A Pacific Spiny Lumpsucker (Eumicrotremus orbis) during my safety stop:
First shot is at 15mm, second shot is at 15mm x 3 = 45mm.
With my 100mm macro, I can now get 300mm of focal length. If I attach my SubSee +10 diopter, it's a crazy amount of magnification.
I pretty much have all of the workflow down and don't really have any issues getting consistent 1080p at 24fps from it. ML RAW for underwater video is an amazing tool. I can't get enough of the quality and latitude. And now I have a super wide angle/ portrait lens behind a mini-dome!