Wheels, it looks like the GoPro in your video has a filter on it. Do you need to balance the H3-3D gimbal to offset the weight of the filter?
Also, since I have the H3-2D gimbal and I want to exchange it for the H3-3D, I see that there is an adapter for the "old P2". Will the plug that was for the H3-2D work with the H3-3D? And, with the adapter, will this extra height make the GoPro sit on or close to the ground when the P2 is on the ground?