personally i prefer the vz navigator because of the versatility of it.  one thing that i like about it alot is that you can change the vehicle types to be car/motorcycle, truck, bicycle or pedestrian so for example if you are walking/biking around a city and want to search or navigate to things and get directions to walk there you can.  i am not sure but i do not think garmin has that feature plus you would need to carry the garmin with you everywhere.  why do that you are carrying your cellphone with you anyway.  besides that i also like the movie and events options and under the maps section you can see traffic alerts and weather for anywhere.  it just really depends on what you would like.