Here is a video taken using the 50 Mbps 108060p MOV mode of the GH3. This mode uses the same sophisticated compression as AVCHD (CABAC, high profile, 2 reference frames, etc.) but packaged as MOV and at a bitrate that is almost twice as high as AVCHD 2.0.
Can you see any difference in quality compared to 28 Mbps AVCHD? You can download the original file (re-wrapped as MP4, but not transcoded or re-compressed):
Perhaps scenes like this (garden flowers in daylight) do not challenge much, but there is plenty of detail to encode).
For comparison, one can also download the original "focus-pull" GH3 video, which was taken in the same place under the same conditions but using 108060p at 28 Mbps (AVCHD 2.0):