I hate the navi in my Lexus. I think it takes me the bus route.
I have a Garmin w/bluetooth from Costco and it works much better than the one Lexus provides. Sometimes, if I really have no idea how to get where I am going, I bring in the Garmin.
With the Lexus navi, you can't add addresses while driving, it almost never takes me straight to my destination, it will say "you have arrived at your destination" and I will be in the middle of an intersection! I can't make outgoing phone calls on the bluetooth, the screen reflects the sun, it doesn't tell me which street I will be turning on to-it just gives me the distance and direction I will need to turn next and the distance is always off and it is MUCH more complicated than it needs to be. I am in Calif, if I go to LA or some other city it automatically defaults me to Nevada. I have friends who said theirs does that too, I could go on and on...I hate it.