I greatly prefer Waze. The biggest annoyance for me was that Android doesn't have a way to default to "avoid tolls", so every time I started up, I had to dig into the settings or risk a momentary distraction putting me on a toll road.

Waze has more of an interactive experience (with the ability to report hazards and backups, and some random reward system), but it is more of a focused app than Google Nav.

But as with anything YMMV (Sorry, obligatory pun)