GPS
Like Bose X I find that the Garmin 430 I have which although coupled to my autopilot and HSI is useful I don't find the button pressing sequence to be user friendly.
Whereas the Garmin 496 that I have on the yoke is simple and intuitive to operate so I tend to use the 496 for map mode and track corrections.
IMHO the 430 is like a PC but the 496 is like a MAC in simplicity of operation.