There is one automotive GPS unit worse than a laptop: the Hertz Neverlost - the Rubik's Cube of GPS's. This unit is so remarkably bad, every design school in the US should have one on hand to show students the perfect example of how not to design an interface for an electronic device. It's really THAT bad. I think they named it Neverlost just to add insult to injury as users pull their hair out attempting to navigate out of the Hertz parking lot at the airport.
http://hertzneverlost.com/