I built a quadcopter with the pxfmini and a pi0. On April 11 2018 it flew for the first time. I started the project in September 2017 and got stuck for a bit connecting to mission planner. Once I got past that and had all the rotors going the right way it was quite a thrill to see the robot hover! I began experimenting with how to get longer flights and was close to mounting an avr microcontroller from PWM 6 to power an IR LED to play lazer tag with a ground based target. All was going well until I changed to alt-hold (I think that's what happened) and the poor drone sailed away not to be found. I have learned several lessons and will use GPS or something next time.
To anyone reading this, if you are stuck, you can do it! And perhaps use PWM 6 for a kill switch instead of an IR LED???