The video is blocked in the US due to a content match (music) - you made me curious about your experiences working with the 4.6K.
Casey is a great reminder that story is more important than equipment. I was very impressed and motivated to get off my butt to create more when he set out the goal of posting a video, every day, for a year. After a year, he called it quits - but not without securing a lucrative deal to create more videos in the process. I think It's a combination of his shooting/editing style and his personality that have launched him to stardom.
Confirmed - 6K anamorphic will be released in a firmware update about 6 months after the camera is released.
I spoke with a Panasonic rep at CES and was told that the GH5 will ship without V-Log and it will still be a $100 extra - so factor that into the price if you are counting on using VLOG. When I asked why it is not included I was told "because it is essentially a consumer camera" and they didn't want to field a million questions from amateurs who were not able to work with log footage. I think that is lame.
If you go for the BMPCC I would suggest the BMPCC specific Speedbooster because the .58 version gives you a wider field of view than the .72 version and also allows more light through (1 and 3/4 stops I believe). The normal crop on the camera is 2.88x so with the .58 BMPCC Speedbooster you are looking at a crop of 1.6704x. I have the Nikon version and it works great. If you are serious about color grading, the Pocket Camera can deliver some awesome images, it just takes a bit longer in post. If you are already invested in Canon glass you should consider the EF version....the only benefit there in my mind is the ability to activate IS. For handheld work I simply use native M43 glass which is sharp and has decent IS. Another thing you need to know before buying the BMPCC is the problem it has with IR pollution - this has screwed me over far more times than the occasional moire. If you are using ND filters, outside in bright light, you will notice that the shadows are tinged with an ugly red which is nearly impossible to color correct. There are several solutions including filters that fit on the end of your lenses or IR cut filters which go directly over the sensor. The IR cut filters are not cheap, but I would seriously consider getting one if you plan to shoot a lot in bright, natural light. I also agree that you might want to hang onto the A7s if you can afford to do so, but I think it is worth giving the BMPCC a try. When everything is set just right the images you can produce with teh BMPCC are spectacular. One last thing.....you cannot set a custom white balance by shooting a white card with the pocket camera. This is, in my opinion, the biggest shortcoming of the Pocket Camera. Good luck with your decision, I hope this info is helpful.
It may cost you a hundred dollars or so more than your desired budget of $650, but as the owner of two BMPCC's and a case full of lenses I can tell you which one I use the most and get consistently great results with is the Panasonic 12-35 f2.8. You can find a grey market or used one for around $800 and it is totally worth it! The lens is contrasty and sharp and just fast enough to be usable indoors. The image stabilization is kick ass allowing you to use the lens hand-held and the range is amazing on the BMPCC it has the full frame FOV equivalency of 35mm - 101mm.