While the Siyi A8 is not perfect, it does work reasonably well with ArduPilot 4.3.x (and higher) and newer versions of both the Siyi software and AP versions are making it better all the time.
If you could post more specifically what issues you’re seeing, ideally over here in the AP discuss Copter-4.4 beta testing category that would be great.
Here of some videos of me using it at the recent AP developers conference.
