I dont use mine that often, but the times I have, its been a life saver..
Re-routing me off a backed up interstate. Looking up phone numbers while on the road. I never had a car with it before, but I dont think I will ever have one without now.

 

Homeslice: Were you shoppin' for a BMW 3-series? That's where the lose-the-changer-for-the-nav options was in '03.