I'm using a Canon 5DIII and have on occasion needed to use a flash bracket. I have a Custom Brackets folding bracket that has allowed me to mount the camera so that the handle on the bracket is on the right side, and I rotate the camera counterclockwise to go from landscape to portrait. The flash is on an arm that flips to the right orientation.
This worked with my ancient but wonderful 1DII, but with the 5DIII it does not leave me enough room to get my right hand in position for reaching the "*" button for focus and the shutter button. I also have a RRS L-bracket mounted on the 5dIII, and do not use an add-on battery holder/vertical grip.
I would consider either a similar flash-flip bracket or a camera-rotate bracket but don't know which to try. It is inconvenient to head for a camera shop that has these on display.
Do any of you use such a bracket with a camera the size of the 5DIII with similar button placement? My wish list includes: Light weight, ease of use, and probably, a way to stand the camera/bracket combo on a flat surface when not holding it. While I would like low cost, I'd spend what it takes to get a bracket I'd actually use.