PIREP: (from a new simmer, see above)
After getting all of the above components connected and functioning, I started X-Plane 12 at my 'home' airport (KCDA) in a G1000 C172, 'engine running.' I managed to take off and fly to KEFK a bit north of there, and land on a straight-in approach without bending the airplane or going off runway, and managed to taxi to the ramp and shut down properly.
During this flight, the SIMiONIC setup (which was what I was primarily testing) worked well. The engine instruments on the MFD returned sensible data, the PFD primary instruments likewise. The only things noticeably different between the Simionic and the software G1000 in the aircraft were the fact that it doesn't seem that control inputs on the Simionic units is translated to control inputs on the software G1000s (which is OK, since I don't need *both* of them functional) when it came to display changes and the like. I didn't test the autopilot functionality, but things like map changes, zoom changes, direct-to and flight path displays didn't match. Not a surprise. The other issue was that the nav data in the Simionics is noticeably lacking in resolution - something they warn you about - for map use. There was no data other than basic airports visible around KCDA/KEFK, which MIGHT be because I had terrain turned off on the simionics, or might be because terrain data wasn't available - I will need to figure that out.
The biggest challenge I struggled with was probably obvious to anyone with experience on setups like these. Both the rudders and stick have fairly noticeable return-to-center springloading. I was having real trouble focusing on the visual feedback from the sim ONLY to determine what the aircraft was doing. Flying coordinated was nearly impossible this try. The lag in response to rudder inputs was noticeable, and is likely related to my computer being underpowered. But while I made it, I won't claim I was flying in anything other than a 'drunken aviator' style. Debating whether to try removing the spring force where possible, but I think that would probably make it worse, tbh. Not rich enough to pursue force-feedback to see if that helps
Next steps - probably parallel tracks. One will be to improve my stick and rudder in the sim enough that I can reduce my 'workload', enough to start thinking about instrument procedures. The other will be to start using the sim purely for G1000 familiarization, because the operation of the Simionic units was flawless modulo the 'light' map data. I have a G1000 training book and will see if I can start working through that. I used a G1000 C172 aircraft several years ago for a cross-Australia flight in the actual world, and had managed to get basic VFR competent on that in a few hours (enough to not feel hampered on the two week journey) so goal 1 is to get back to that level of familiarity.
Oh, I ordered a more substantial bezel/stand to hold the G1000 units, from
AllSports Systems - will report on that when I get it. It looks sturdier and more easily moved than the flimsy/sharp metal stand that the Simionics ship with, but is relatively cheap since it only holds the Simionic components and doesn't include or have room for additional controls. I'm still looking for a way to simulate a complete DA40 panel, but that's definitely a more long-term goal.