Active track seemed to work ok but I found it a bit sluggish. I decided to ride my electric unicycle to see if it would keep up with me. It lost me several times when I was directly below the bird. It seems that the drone will allways "fall in line" behind the target as the target moves. I hope there is a way to film from the sides or front. Also interesting to note that you have limited control of altitude during AC. But when you do go higher the P4 is actually moving up AND backwards and maintaining the exact same angle to the subject.