We had an IFR-LongRanger in Switzerland for quite a while. No dual hydraulics, I think not even dual generators. Bigger battery I think. It worked. Did not fall out of the sky.
And by the way, flying a Robbie even in simulated IMC is a lot of work. Remember? No autopilot like your fancy twin.
And I still think the only way to really fly helicopters is in the mountains with a load underneath. IFR for helos is like flying planks. If they could build runways on a rigg, they would do it and get rid of all the helos.
