Ok, this is what I have done, started the TBM overhead an airfield at 3000 ft at 120 kts (glide speed), ISA and no wind, and cut the engine / “feathered” the prop. I then made a glide with 120 kts down to the ground (SL), paused the sim and measured the distance traveled using Bing maps (attached).
I managed to travel 16.9 km which equals 55432 ft, this means the TBM with unfeathered prop has a glide ratio of 55432 / 3000 = 1:18,5 or 328 ft per 1 nm, this seems unrealistic to me, I doubt the TBM would be able to glide this far even with the propeller feathered…
It’s unfortunate that there is no such data available from the TBM POH.