The turbo-prop conversions are certainly less maintenance intensive, simpler to operate and generally much more reliable, but not really cheaper to operate , the exorbitant cost of the engines and conversion has to be paid for somehow.
They look very ungainly with the big fuselage plug needed to get weight and balance right.
Even though in task specific uses they can perform very well, I personally don't like them, I think there have been four different conversions by different companies, including SAAF military version and the few RR Dart engined ones, some are more (less?) ugly than others but they all look wrong 😎
Original ones can be fairly cheap (comparatively) to operate but finding the right experienced/skilled maintenance crews for commercial operations is getting increasingly difficult, even if financially viable in countries where there is work for them.
Hope our C-47 follows the Ju-52 product model and is made flyable in the future