Avidyne

For me the IFD's are much more user friendly and capable than the 430's they replaced. The learning curve is shorter with the training app, the F. Bauer book and training videos provided. I felt comfortable before the units were installed. The intelligence of the comm tuning along with the facility id really cuts down on single pilot IFR workload. Approaches are easy to enter and the interface with the new DFC90 and older Avidyne PFD is good. For approaches; I use the SVS on the 550, Map on the 440 with Data visible on both units and charts on the MFD. I do like the charts on the 550 and usually have the briefing strip or profile up so that simply pressing MAP remind me of minimums and missed procedure.
I really prefer the knobs inflight when it is turbulent. Flight plans are easy to enter and amend although the windows for crossing restrictions, holds, etc are small and best done with the knobs. The app and blue tooth keyboard can be used also, but my instinct is to do everything on the unit itself.
So far I have had no issues except a database loading issue which was handled by tech support quickly. Other than the one issue database loading has been easy. It's not unreasonable to do nav and obstacle databases while doing cockpit set up after start but charts take longer and are best done before a flight on ground power.