Gh4 shot in 4k/24fps. A7s was 1080/30. Both are great gimbals, the difference is price and payload, you can't go wrong with either, if you want to use with DSLR cameras, consider the Moza Air, if you are using mirrorless, Zhiyun Crane should work.
Our Air was a preproduction version and we did discovered the pan to be a bit jerky and adjusted the settings now.
Crane is at $650 where the Moza Air is $599
More info about Zhiyun Crane visit: http://zhiyun-tech.com/
More info about Gudsen Moza Air visit: http://gudsen.com
In the meantime, check out this article review: http://mdifilm.com/2016/2017/04/11/gu...