Jaba. They were a special purpose aircraft - as is that machine - and they do that task well.
Unfortunately in charter or RPT, nine seats won't fund the capital and maintenance cost of two Allison B250's. I vaguely recall the Turbine Islander also had less endurance, and over a 100 mile plus sector, less payload than the piston Islander due to higher fuel burn?
The best part of the Islander was the Lycoming 540s, the rest was fairly maintenance intensive. The BN2A Mk III Trislander was Britain's revenge on the Empire!
Tins. There were many BN2A-M's in the Torres Strait. Some had very questionable histories......