The balance of safety against probability of occurrence is a tricky one, and when we make it for ourselves, we almost never spend more than absolutely necessary. When we spend someone else's money, the decision gets a bit more theoretical, and easier. There is no demonstrable difference between the safety record of turbine singles and twins when both are operated by the same type of crew. All the interesting discussions about engine failure tolerance and HV curves does not protect a pilot against the cause of 75% of the helo accidents - pilot error.
Question: How many ppruners have turned their old cars in specifically to get anti-lock brakes, 6 station air bags and similar safety features?