None of them are that accurate and that includes Google and iPhone... Think about it, any idea how many map changes happen daily? And unless your Google Maps takes several hours to update, you are only getting some of them. Nature of the beasts. I have had Garmin take me miles out of my way, and put me on a runway WITH a plane. After an update. Mazda only updates 1-2 times a year and of course it is not up to date.
I will continue to use Mazda Maps or Nissan NAV (on my truck) because of ease of use and size of display (my old eyes). Oh and to be sure I carry, egad dare I say, paper maps!!!
Use what YOU like and deal with it!!!
DEEP CRYSTAL BLUE
2016 CX 3 Grand Touring AWD