Originally Posted by
Andy
No experience with VP-X but do have experience of using G3X Touch and of modifying the system to add capability.
Think carefully about redundancy and what you need to have working after various system failures. You will likely have only one GDU. If that fails you lose control of everything that is controlled by it. That could include remote COM, remote transponder, VP-X power switching, or more, depending on your chosen configuration. You don't only lose control, the remote devices may reconfigure e.g. COM switches to 121.5 MHz.
As I have posted previously I would not fly at night or IMC with a only a single GDU. I consider a second attitude indicator to be essential unless day VFR only.
The G3X Touch system is very capable but, with a single GDU, you have a lot of eggs in one basket. A full system would have 2 large GDU and perhaps also a smaller GDU acting as an MFD. Now you have some redundancy and the Garmin failure reversions make more sense.