The first battery flew off with a bang. I put the second one - the quadric itself flew off to the side, stopped "obeying", then abruptly went up and - into the forest. Are they specifically programmed that way? Or do you need to check the trim settings before each flight? Different pros: Quickly figured out the controls. He flew around the apartment, in the yard. Cons below: I went out into the open, near the city stadium, near the forest.