whilst the -41/-42 class of engines in the Piper PA46-500TP had not?
Ok interesting.
which combined with the aforementioned abysmal performance as a commercial machine probably alludes to why someone else hasn't already done it, if it's even possible.
yeah totally agree, it's a rich man's toy for sure - can hardly lift anything. However, there are slightly less rich men that do not own an aircraft, but would pay happily to be flown from A to B in turbine aircraft at less expense than taking a King Air, hence the question. Not asking because we are choosing between PSEA aircraft for a purely commercial purpose, there's no way you'd get a PA-46 with that reasoning.