It's weird, the display often shows Google maps, but navigation is clearly using bad data or a bad service because often times the car picks the weirdest path.
For instance, in Texas FSD will almost never take the underpass u turns, and instead take the lights just because that's what the navigation said to do. Once i manually get into the u turn underpass lane, the navigation updates and FSD has no issues.
Another thing is parking lot ghost roads. The display clearly no road being there, but the blue navigation line insists something is there.
Another thing is real roads that are there that the navigation doesn't think is there. TomTom doesn't think a section of road in my suburb exists, but the car display clearly shows the road. And the navigation always reroutes around that section of road which makes me believe Tesla is using TomTom for navigation.
I think Tesla needs to build their own mapping service or just use Google for navigation.
Other than that, FSD has been basically flawless(it did crash/ shutdown and reboot itself in the middle of the highway, but hopefully that was just a bug that can get patched)