Interesting seeing a comparison between two shots with one camera without it and one with. I see the operator with the gimballed camera having a hard time keeping the subject in frame as he moves. The lag is the problem, maybe one could learnt to compensate?
Apparently you can buy this system completely assembled from DJI, the makers of the Phantom 2 Quadcopter and other multirotor copters. Here's a promotional video they created showing how this can be used to record a complex one-shot scene in a movie.