my wife be a personal assistant to a commercial real estate developer and a great portion of she time be spend run errand in area she be not familiar with . she have tell I of some close call she have in the car , as a result of travel slow to read street sign or address number . on other occassion she be delay when she have to stop to phone the destination and ask for direction -lrb- one of the few who will not talk on the cell phone while drive -rrb- . with the Garmin c340 she be able to give all she attention to drive , keep pace with the flow of traffic , and not experience delay to stop and get direction . she say she have reduce she errand time by 30 % , and reduce she auto expense by 10 % . I be a bit frustrated when I find the unit come with a quick start manual and you have to go to the Garmin web site to down load the full instruction manual . my wife be not concern as she have never read a instruction manual for anything and usually toss electronic gadget to I to figure it out for she . this thing be so complete and simple to use you do not need the instruction manual . I have to show she twice where the on\/off button be -lrb- one of the most prominent feature on the side of the unit ? -rrb- and then I go to download the manual . she keep come into the office to show I what she have learn to do with this thing . by the time I have the manual download , on a dial up line , she have figure everything out so I never read the manual ! I originally start look at the gp because a friend , who be a electronics wizard and write computer program for video game , have a tom-tom . he come to visit about two week after we receive the c340 and my wife be show he all the feature and he sit there with he tom-tom and keep say , `` Mine do not do that ! '' he call a week later and tell I that he know I be a little disappointed because my wife take the Garmin , and toss I she new road atla , and he offer to sell I he tom-tom cheap because he replace it with a Garmin c340 Streetpilot . the review , I read on Amazon , which inform that this unit tell you the street name of exit give great influence as to my selection of this unit as my wife travel to California for she employer , and we have relative in San Francisco . we now travel there and navigate the traffic like one of the local . in summary : I research every gp I could find for three month before purchase and the c340 be the most powerful at the affordable price ; this unit will pay for itself in reduce drive expense , at today 's gas price , in about 6 month if you run daily errand ; insurance company should give reduce rate to driver who have a gp as it allow you to focus on you immediate surroundings and not impede the regular flow of traffic .