I buy this before a trip to California that take we to San Francisco , San Jose , Santa Cruz , Lake Tahoe and Yosemite NP . this be the first time we do not plan any segment of a trip , or print drive direction . therefore it be a big risk , especially for someone suspicious of technology . after the trip , I have to admit this device have spoil I . all those thought that get I stressed while drive , e.g. , `` which direction be I drive ? '' , `` what be the name of that street ? '' etc. , be go . toward the end of the trip I be make turn without even check the name of the street . if I miss a turn , it would reroute very fast . I be a little nervous about how it would work in the wilderness of Yosemite , but it be accurate throughout . even the rapidly fluctuate speed limit on the wind mountain road -lrb- e.g. , 45 to 25 to 35 to 20 to 35 etc -rrb- be accurately display . I do not know how well it will work in future trip elsewhere , but base on this one long trip I highly recommend this device . I can not wait to take it to we next trip .