Can Use Pixhawk 4 with audopilot by changing the firmware?

#1

I am using pixhawk 4 with Qgroundcontroller. can I change it to Audocopter? whether it is good in all aspects?

#2

To flash arducopter:
http://ardupilot.org/copter/docs/common-loading-firmware-onto-pixhawk.html

To flash PX4:
https://docs.px4.io/en/config/firmware.html