As for the TBM 850, it is a beautiful aircraft with a well shaken down airframe BUT has half the svc ceiling and costs twice as much. You will still be flying through a lot of the Wx that the Eclipse will be going over the top of.
Not sure about "half" the ceiling, SB
The 850 does about 30,000ft. Only the Concorde, or mil jets, could double that.
I have no axe to grind because a) I am happy with my TB20; b) cannot afford a turboprop anyway (other than some really knackered Meridian with bicycle tube patches all over the rubber boots); c) wouldn't buy a TBM anyway, preferring something much slicker like the Epic.
But a 30k ceiling gets you above all stratus, above just about everything except CBs, you can avoid embedded CBs because you have radar, and only a 50k+ ceiling will get you above turbulence. In terms of clinical mission capability (the go / no-go decision) I don't see much difference between 30k and 40k-45k.
And neither has the ~500kt TAS to get you airliner-type upper airway routes.
The jets will definitely sell, but I reckon 1/10 to 1/5 of the figures banded about. Especially as a lot of the sales are based on US air taxi fleet purchase projections, which don't add up if you allow for six fat Americans turning up with their golf clubs. Or six fat Europeans for that matter; the Brits and Germans are not far behind.