Edit: I had replied on the previous thread and hadn't noticed that you had posted both threads. So, some of this is rehash of what I said on that thread.
I'm a fan of Zeiss for video for both the look you get and the mechanical operation of the lens.
Having the Zeiss 50mm 1.4 and 85mm 1.4, you really don't want to shoot these wide open if you have a high contrast setting. If you do, you'll get quite a bit of purple fringing where dark objects are against bright objects (see sample video below). This is a fairly well known characteristic of these lenses (i.e., I've read others' comments along these lines). You can get rid of it in photos and less easily in video. In my experience, the fringing is gone near f2.0. Something to consider, however is that the depth of field is so shallow on the 5D3 at f1.4 that you are likely to lose focus on your subject in video anyway (I'm assuming that, since it is video, your subject is moving). Of course, this applies equally to the Canon and Zeiss. Still, I admit that 1.4 or 1.2 is nice to have. Finally, the Zeiss 50mm 1.4 is not as sharp at 1.4 as at 2.0. I can't say about the Canon 1.2L, as I haven't used that one, but usually...
I also have the Canon 24mm 1.4L II and I personally don't care for it for video. The objective part of that statement is the mechanical operation of the lens, with my primary complaint being the focus throw and lack of hard focus stops. Zeiss lenses are generally better in both regards. Subjectively, I simply feel the look of the 24mm 1.4 is not as compelling as what I get with either Zeiss lens. This could be a focal length issue, but I'll be selling my 24mm 1.4L soon to get a Zeiss 25mm or 28mm.
I shoot mainly video. My wife shoots photos. She finds the manual focus of the Zeiss to be fine, given the focus confirmation that you get (she shoots a 5D3). But, she doesn't shoot fast-moving subjects. She also really likes the weight of the Zeiss 50mm 1.4 and feels that it balances well with the 5D3.
If you can't live without autofocus for stills, you might consider the Canon 50mm 1.4. We also have that and it is a very nice lens and, in my opinion, simply a great bargain. Regarding manual focus for video, it has a long focus throw, but still doesn't have the hard focus stops. I would actually rate it as sharper at f1.4 than the Zeiss, but not necessarily so at f2.0.
Here's an example of the purple (and sometimes pink) fringing that I've experienced with my Zeiss lenses (in this case, the 85mm 1.4). See examples 0:58 (purple) and 2:04 (pinkish). As you can see, you can address this in color grading, but...
https://vimeo.com/40356472
