I certainly had hopes that Canon would go quite a bit farther with the M system, I own the current version, not a bad Camera, but not a good camera either when I look at what it needs to be a reasonably developed back up to my 1Dx & a possible replacement for my 5DMK III, the current M doesn't do it.
But the Image files aren't too bad from the current M, absence of a viewfinder is a big issue for me after having the current M, in day light the screen is almost useless.
So, my a7r arrived 3 days ago, still trying to work through the Menu system, not as bad as the Nikon System, but takes a while to work out.
Nice size, has a viewfinder, takes some getting used to but I like the viewfinder on a7r.
I was concerned after reading reports that the auto focus would be quite slow, but I'm using the a7r in dim lighting, very dim, and it focusses just fine quick & accurate. Files look very good to date but I'm yet to really put the is camera to the test considering the choices of Lens, well, make that choice, in Singapore the only Lens available is the Zeiss 35f/2.8, which is a lovely Lens, 55 arrives sometime late December.
Once I get a WA ( 15F/2.8 ) & a Macro ( 100f/2.8 ), I'll try & get the a7r into a Underwater housing, I have high hopes the a7r could replace my 5DMK III for underwater Imaging.
Like the Camera so far, has a load of the things I had hoped Canon might put into V2 of the M.
Image was shot with the M.
Thanks for the input regarding the Sony...I cannot buy one...but I am eagerly watching the development of all-things mirrorless.