"Has any of you done the upgrade to your systems and is it working?"

I've upgraded my G900X to system software 10, and while the baro and current altitude settings are transferred to the Sorcerer from the Gramin, the selected altitude is not.  I examined the G900X's documentation for the data being sent over the serial line from the G900X and I don't think the selected altitude is being emitted by the G900X (and therefore can't imagine how the Sorcerer could deduce it).  Or maybe Garmin's documentation isn't quite up to date.  In any case, I can't get the selected altitude to transfer to the Sorcerer either.

The selected heading *is* emitted from the G900X, and sure enough my EFIS works as a fine "external DG" for the Sorcerer.  You need to push the "EXT" button on the face of the Sorcerer to cause the Sorcerer to use the G900X as the DG.  If you don't have an "EXT" button on the face of your sorcerer you may need to send the Sorcerer back to TruTrack for an upgrade (as I did).

This all worked in G900X system System 9, too -- I think System 9 is superior to System 10.  They've added some sort of "dampening" in System 10 to the fuel flow reading.  It's now impossible to do the "big mixture pull" for LOP and watch the G900X's fuel flow gauge to know when to stop.  There's literally a 5 to 10 second lag in the G900X's fuel flow indication.

-isaac
N7942K