I just bought a second hand Video Assist 4K to use with my Panasonic GH5’s. I love the Video Assist 4K thought to be truthful they are heavy on battery power, I tend to use them on mains power when I can. Stupidly like many companies they use the Canon LP-E6 Lithium-Ion batteries that are not beefy enough for the job instead of using good old Sony “L” batteries.
Both my site partners H Preston Media and Production Gear sell these monitors.
I also have the BMD Video Assist 4K and it is indeed a very good monitor/recorder and even an audio recorder although I’ve never used it as such. As you say, it is very heavy on batteries. I have found an adapter plate that allows me to use Sony L batteries.
I also own the BMD 5″ monitor which I use with my FS5 and A6300. I find the battery life on this monitor is far better than the 7″ monitor, which I suppose is to be expected given the small screen real-estate.
The battery option are what really let this down.
Small HD went down the user swappable battery plate a long time ago. Atomos use NP batteries for almost everything.
I’ve got 21 NP batteries currently in use, so I won’t be buying a different system. So many LED panels, and adaptors use NP.
Someone needs to produce a fatter or deeper LP-E6 compatible battery for this and other monitors.