rig, the problem with the Thielerts is the interface between the engine sensors and the FADEC, rather than the FADEC itself. It's a very new system and there are some creases to iron out for sure, though how that'll happen now Thielert have gone under is a moot point.
Also stretching the Mercedes 1.7L diesel lump from the original 100Hp to the 135Hp continuous that it's rated at in the aircraft is asking for problems. I've seen everything from turbo pipes bursting to total coolant loss. But these are all engine issues rather than FADEC issues.