Overhaul Costs?
Not knocking the Airvan, but I don't see the economic sense in using the Turbocharged version unless you really need the altitude capability.
From Lycoming, a rebuilt-exchange engine for the turbo version runs $76,992 USD vs $48,955 USD for the normally aspirated version.
I don't know the TBO of these engines, but imagine the turbo version is probably 100-200 less?
That's big chunk of cash per hour!