We're heading over to the States for a road trip in April and over here I have a Navman GPS in the car. I was thinking of buying the U.S. map to put on it and use it over there. My question is do any POTN'ers use Navman GPS's and are the maps / directions good? Over here they can be a bit iffy in certain spots - i.e. doing point to point highway it may try to send you down some suspect dirt backroad instead of the main highway.