And even if I went with a Sony body (looking at A7S for video) I'm not ditching Canon glass. No way. God Bless Metabones.I got an a7s for video (mostly school plays), and had my first chance to use it last week.
It is literally unbelievable how good it is. I recorded some auditions at ISO 1000, F/4.0, 1/50th, and the image quality is outstanding. I used the Metabones adapter version IV, the Canon 70-200mm II IS, and the Canon 1.4x extender.
Simultaneously, I had my new 7D2 going at similar settings. The constant auto-focus is great, but the picture is mushier.
I love the a7s for video.