I have use the optional nav system that be a $ 2,000 option in most car , and the Garmin c340 be by far the easiest and best perform nav system I have ever use , at a fraction of the price . it be so user friendly that all I have to do be turn it on and go . the amount of datum pre-loaded into the unit be stagger . my relative that live on a private road with only three other home be in the system . the other system I have use could only get I to a intersection , about a mile away . my only regret be that I do not spend a little more to purchase one that be bluetooth ready . I be thrill with my c340 and purchase it on Amazon.com be easy and fast .