This video is actually very helpful. Its been a while since a truly insightful video was posted. Thanks!

Sadly, this is NOT a follow focus system. This is JUST the gear ring. You will still need that 1.5k FF system. I pay 10-20 bucks for custom made lens specific gear rings. 300 bucks for a gearring is insane and will most likely kill the product before its even launched.

"Ah damn, crashed in that blasted river again..."

As someone who solely uses V-mount batteries I've never had one 'just falling off'. Sure, an intern once hooked it up crooked and he dropped it after that...but thats just clumsyness. Once they are in place...they stay in place.

And there are TONS of brands who make them....

Found an interview about the lens. They say it's 'near' parfocal, but not 100% parfocal. What this means in real life for say...zip-zooms...We'll have to wait and see i guess.
https://vimeo.com/182048909

Even if they only adjust the case - with teeth and the right ammount of throw, and some added rigidity from a metal case i'd buy at least one. Such a fan of the sigma 18-35, so a rehoused one is fine by me! (of course, parfocalness would be a great addition)