Read more about Joe's thoughts on the GH4 and his setup with a click on the link below.
In viewing the video, please note it's in 4K. For you the viewer, the default resolution may be set lower. You'll need to select a higher resolution (2160) if desired. Just click on the YouTube "tool gear" and select the higher resolution. Unless you have ultra fast internet, the video will not play without buffering. (Sometimes you can coax it to preload and then play it.)