Hi all, Chiming in a bit late on this thread... I moved from a Canon 550D (S&S housing) to the 5Dmk3 with the Hugyfot housing recently. Regarding the camera, I confirmed what the others said earlier, the autofocus is extremely fast and manage to lock-in accurately in very low light and with fast moving critters. The IQ is really good IMHO, but then again I moved from the 550D so not sure how it compares to the 5Dmk2. I am also very happy with the video mode, and find it very easy to switch back/forth from shooting to recording. In that regard, it is quite cumbersome to set the manual white balance, which is a bit of a drawback as I usually do that many times when recording videos during multilevel dives. The programmable shooting modes are a great feature, I recorded a setting for macro, wide-angle, and video and I end up only using these ones in the last couple of months. I am very happy with the Hugyfot housing for the 5Dmk3. First the people at Hugyfot EU and the local dealer in Australia were very helpful during my decision process, they answered promptly lots of my emails, giving details and options for what I wanted to get. So even before buying the housing I was already very pleased with the manufacturer and local dealer support for the product. The housing itself feels sturdy, I like the fact that the vacuum leak detector is included by default (so no extra $$ to add it) and given the price of the camera and attached lens I feel less nervous when getting in the water. The housing controls are at the same position as one the camera's body, I know some people like housing which ergonomic re-routed controls, but I prefer to have them in their original place as this is what I am used to when using the camera out of the water. The entire setup is a bit heavy out of the water when doing shore dives with long walks, but I guess that would be the same with most other housings for this camera. If you would like to look as some samples from my 5Dmk3 + Hugyfot setup: - here is a video I recorded last month with the Canon 8-15mm Fisheye: - photos with the Canon 100mm Macro: http://inbetweendives.com/gallery?s=2014-05-10 - photos with the Canon 16-35mm Wide Angle: http://inbetweendives.com/gallery?s=2014-07-27 Cheers, Thierry.