Hello!
> Just curious..as I have never flown one...what does the SAS system do?
I know nothing about the Merlin, but in the Metroliner (a development from the Merlin) that I fly, SAS stands for "Stall Avoidance System" and consists of two AoA (Angle of Attack) vanes, some circuitry, an AoA indicator, a stickshaker and a stick pusher. I cannot imagine that a Merlin has the other kind of SAS (stability augmentation system) described above, apart from a yaw damper.
Greetings, Max
NB: If a Kingair is too expensive, a Merlin could be an alternative to the Cheyenne. They are comparatively inexpensive and offer good performance, but they are certainly not aeroplanes to be flown single-hand by people who come straight from the Seneca...