mister b - You are correct, I think, although those designs would be an example of a single with an extra engine added, almost as an after-thought, but to meet a requirement relatively cheaply.
As mentioned, I was really referring to more recent designs, i.e. 1990's or later, where the benefits of significant rotor development & understanding have been seen.
I think you'll find that the Seaking would not be considered as "optimised" for powered flight, as rotor design has come on a long way since the Queen of the Skies was originally designed!
The Lynx, however, would be an example of an upgrade in rotor design that improved powered efficiency but, if I understand it correctly, made autos a little more interesting . . . though still not practised to the ground.