You would be hard-pressed to find any commuter operation in Europe that still uses aircraft with no autopilots. Why? Because the rest of the world knows that autopilots significantly enhance safety in critical phases of flight. This is especially so in aircraft with relatively low performance to start with
They took IFR approach certified GPS's instead of the autopilots.
I wouldn't say the B1900 is low performance for what it is asked to do, even relatively....