I haven't built a gimbel yet for the GH4 so obviously I haven;t flown it, but I've used it twice just to see how well it works.
This first video was shot when I literally took the camera out of the box, surfed the menus just long enough to switch to 4K, everything else is default. This was shot entirely hand held, I wanted to see how well the IOS worked on the 14-45 lens. Its kind of slow, we had a couple of students from Honduras so I shot part of their lesson.
This second video I changed to CineD, added zebras to see how helpful they are with exposure but for the most part still default settings. I agree with Kloner, in 4K the color is a little thin. I did a quickie correction in Resolve but my first impressions is that this is a fun camera to use and the 4K has a lot of potential.
Sorry this was shot when my wife and I went to breakfast, its pretty boring...
Make sure you choose 720P in the Youtube settings. I can't figure out how to make it default to that when the video is embedded.