Received my panel from SteinAir today. All cut out with rails and screw sockets installed. Only had a couple of issues with it, undersized holes, my fault on the dimensions. Nothing a little filing won't fix. Actually, only one hole (Keyed Master) was a tad too small as well as the middle bank of switches. The switches went in but with a fight, I can ease a little off the sides and they'll slide in as the others did. I'm happy with the layout and the next step is to order the missing avionics. The panel was sprayed with gray primer, I've not decided how I want it finished yet.
So, the two large holes are for Garmin G3X 10" screens.
The center top is for the Garmin GMA 245 Audio Panel
Then the Garmin GTR 200 COMM Radio
Then the Garmin GNX 375 Navigator
The bottom hole is for the Garmin GMC 507 Auto Pilot
I have a second COMM radio GTR 20 remote mounted in the back behind the baggage compartment.