Polish Air Force has them for years. The last airframe loss was in 2002 IIRC (it wasn't exactly helicopter's fault) - a lot of luck and no human losses. You just have to fly/maintain them by the book and use original spare parts. If you don't, it's asking for troubles like on any other machine.
Going back to AW101, I just wonder how the new Mi-38 will compare to it. They are wery close comparing MTOW and dimensions, but the latter is still just a prototype.
By the way, if someone is interested, the public part of NAWSARH requirements is accessible here:
http://www.regjeringen.no/upload/JD/...092011_web.pdf
Arrakis