For your subject matter I would have thought of other cameras, one being a Leica M model and maybe the other being anything in a smaller/lighter body. I have noticed over the years that large black cameras and lenses draw a lot of attention. If I walk around with anything that looks to professional, especially if it has a honking big lens on it, everyone sees me. If I walk around with an old small camera hanging around my neck no less, that does not look very new, most people ignore me. I think for documentary people photography, the best bet is to know your light and be prepared to shoot without having to rely on a do it all electronic camera that gives you too many possibilities, or more to the point, too many options to screw up. Let's say for an example that you've got the camera set to program where it chooses the shutter speed and aperture. In many instances I wanted a different aperture or shutter speed. In situations where time is of the essence, looking into a viewfinder reading small diodes and thumb turning a wheel, (which one, on the front or back? and which way?), takes my attention away. But knowing my light and walking into the scene, or watching the scene evolve, with the focus mostly preset on a manual camera allows me total attention involvement. All I have to do is raise the camera at the right time, maybe make a small adjustment in focus and snap. Now, if your using a long long lens to practically stalk people it's another deal. But you might want to take a lesson from the masters of the past, they choose small quiet cameras for a reason and they learned how to operate the camera without the camera operating them. Knowing your light is the other important point.
This is absolutely correct!