Never flown anything with FADEC. My instructor has - she did a license revalidation flight with someone whose aircraft had FADEC. She liked it - but then one flight doesn't really give you a very good idea, especially with regards to emergencies.
The Europa I fly also relies on electrics. Not quite to the extent that the engines you're looking at do - all it needs electrics for is the fuel pump. It has two electric pumps, one of which is connected directly to the battery, and the other is connected directly to the alternator. The idea is that whatever goes wrong with the electrics, at least one of the fuel pumps will continue to get power.
There are only two scenarios I can think of with this setup which could cause a problem. The first is avoidable - that's the scenario where the alternator fails, the pilot fails to notice it, and in time the battery goes flat. The second scenario is an electrical fire which results in the pilot having to shut down all the electrics. With enough height, it would be possible to pull all the circuit breakers except the fuel pump(s) and then turn the master switch back on, but more realistically you're going to be doing an engine-out forced landing with smoke in the cockpit. Scary - but we take risks every time we fly, and the increase in the risk is small enough for me to not worry about it.
FFF
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