In the aviation world all these electronic gizmos are called navigation aids , with emphasis on aid. If you want to be directed on exactly your preferred route take the time to plan it on a map first and program some waypoints into the GPS. GPSs are only as good as the mapping data in them and I think most of that comes from a common source. They may not be perfect but they sure beat pulling over and studying a street directory.

Becca72 - you might consider hiring one for a short term to find what you like