I would imagine that Dauphine would be a bit expensive along with anything but an R22. The PN68 and 337 would be lighter on the economy scale for running costs hence the popularity for such operations in Vic and they pass the tick for being a twin engine. Operating in often hot and high conditions the second engine would be reassuring. I'm led to believe that the 337 is the aircraft of choice for Life Safer ops due to the belief that in an engine failure / ditching that with the wheels up she will land safely on the water if required (due to the boat liek shape hull), versus a conventional twin, especially given the lower than usual altitudes.