After flying aftermarket batteries designed for BB1 I would land thinking that I had used all the battery, but it hasn't fully drained yet and triggering low battery alarm and landings. This is a problem of BMS that they add inside the aftermarket batteries. I have discovered that Parrot made the mini tamiya male connection very good quality, that is already inside the Bebop. The problem is the aftermarket batteries that are designed to be used with this drone have very poor connectors. After time the connections to these tamiya style plugs loosen and begin to arc giving problems to power in general, motors, battery drain telemetry, sensors GPS and others. In the next couple of weeks I will show you that the mini tamiyas are not even crimped properly to the wires and the metal is extremely thin. The aftermarket batteries may even have over discharge protection in it. Why have 2 BMS? One in drone and the other in battery? That is messing with your flight time. Another problem I found is that the wires are about 16 gauge! But don't think about installing fresh new wire in the drone, 16 guage is all you can get up through the two holes that go to positive and negative. And the holes are barely big enough so you can do that without stripping the silicone coming up. Change connectors and use pure 3s boardless lipo batteries!