Am I missing something?
Why not just buy a cheap Garmin or Tom Tom? Just for the Waze benefits (cops / cameras)?
Cops and cameras are part of it, I've had my life saved more than once by being alerted to objects on the road (no lights on the highway, once was an aluminum ladder, the other time an unidentified LARGE object), animals nearby warning is also very helpful.
But beyond that, the accurate traffic patterns and re-routing is unbeatable, and to be honest, the maps themselves and directions are just a whole lot better than Garmin. To the point where I can't use my old garmin anymore, even as I try to get another Waze device, because I just get annoyed at it. It's like a "you had one job" meme.