I have an inexpensive (about $200) Magellan unit mounted on my dash.
It is similar in size and appearance to this one.
[img]
http://www.magellangps.com/en/products/getProdImage.asp?PRODID=1016&ATTR=ProductImage[/img]
The biggest benefit I receive from it is that it will display the street name I am on along with the street name I am coming up to. In the Boston area many streets are missing signs so I find this a big help.
So with this GPS and a map book or Internet directions I get anywhere easy.
I have also used a very nice $1,200 unit with a large touch screen display that also 'talks' to you telling you when to turn if you punch in your destination.
[img]
http://www.magellangps.com/en/products/getProdImage.asp?PRODID=955&ATTR=ProductImage[/img]
It was excellent, I really liked it. It worked almost flawlessly on a 3 week work trip through a few states and many destinations.
It's data base included small dirt private roads, restaurant and hotel chains etc.
I could punch in the words Dunkin Donuts and it would list the nearest 100 locations. How can you beat that?
All that said IMO it is not worth the extra $1000 over the one I own. I can get to the same place. I just have to read instead of listen.
If you have the $ and like gadgets the $1,200 one is a great toy...er I mean tool.
Bob