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I'm thinking of buying this $70 laptop GPS adapter from my local Office Depot:
http://www.officedepot.com/ddSKU.do?level=SK&id=643715 .
The main advantage to these adapters is the large easy-to-read-at-a-glance laptop screens. The main downside is the large
overall size compared to small dashboard mounted units. The laptop normally has to be on the adjacent seat, the floor, or the "navigators" lap. It has a USB antenna module, that is about the size of a small cellphone with a slim cord attached, that needs to be on the dash or rear window with clear sky access. The computer GPS would be easy to update but it hasn't really needed it.
My wife has a similar Garmin adapter (about $110 a couple years ago) and it works fine, even with the computer cover closed on voice only. With a destination selected, the voice-only mode periodically repeats the distance to the next turn until the last 50 feet or so. If the expected turn is not made, the computer immediately re-calculates and re-directs you to the next available re-route and turn (or the next etc). It would be pretty hard to get lost with one of these, even in event of surprise road construction or sheer brainfart. It seems to be accurate to within 10 or 20 feet and be equal to (or more elaborate than) more expensive units.
Many hotels, fuel stops and restaurants are pre-entered by name for quick destination selection. Otherwise virtually any street address can be entered and the computer takes over using GPS to direct you, tracking (you, the arrow) on a zoom in/out detailed map screen ...and/or voice. When my wife purchased it, all but 2 month old streets in Bismarck, ND were already entered, named and plotted on screen map, so I would assume it would be very accurate nearly anywhere.
I have to say the large screen, excellent software and reasonable price tend to spoil a person.
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