No offense, but single or twin PT6 engines are about the most reliable turbo-prop engine out there, as far as comparisons to PC12's/TBM's to any twin. Just my 2 cents.

As far as the corporate 1900, both Meijer and Menards use these planes for corp shuttle duties, and they have a nice baggage space in the rear also!!!

If you're going to be light loading, why not stay with the more common Be20 or 350? Easier to crew, cheaper to operate, better looking, etc... I don't know the speeds on the 1900 either.