Built a couple of them and they both worked. However what i found in flight was that the cables were a pain, as is any external wiring in the cockpit.
Only Aerial and power but still a pain. Earlier RPI S had issues with overwriting code at shutdown, i hope they have sorted this out by now. As a side issue i also find the RPI a confused beast, powerfull but restricted in many ways because the ports are not always full words or bytes wide.
Ps used ozrwys software and from inside my workshop at near sea level it had a range of around 30 knm. Trimmed and adjusted the aerial length to get what seemed the best result. But for all practical purposes you need not do this , you will get sufficient performance once in the air.