I have been flying a GX since late January -- the one word that comes to mind is "fantastic!" Previously I flew a legacy 407.
Faster to get launched as flight plan info is entered prior to start, much simplified power management with the single limit display, fantastic SA info flying in the mountains. The HITS boxes are wonderful flying under a low ceiling over the water.
We have had zero issues with the G1000 installation, and we were one of the first few GX ships delivered - Bell and Garmin really did their homework.