I have a Denso unit in my Lexus and it's GREAT! Can't believe it even works inside parking garages. Seems to update about once a second and boots up in less than 3 seconds. I understand both these things are issues for the Z_ units. I saw a pic of one in a GTM somewhere, so I know someone has used it. What about the phone and other features? Do they work? What else have you tried?