I would get the Delorme. Be sure, if you get either that or Microsoft Streets and Trip that the pkg includes the GPS. Right now I have MS S&T w/o the gps. (Thought the gps was sold separately.) The difference is that you just map out the route without it, but it guides you all the way to the door with the gps, by updating your map as you go. (You don't have to zoom in or out manually.) When it's about time for you to make a turn you have time to move over if you have to. If you miss a turn it guides you back to correct it. Can get Delorme at Circuit City.
Seems I heard Delorme was also more accurate.
If you don't have a laptop, consider it before a GPS system unless you can afford both.
With a laptop you can download games, play DVD's, CD's, and go online.
By the time you buy a Satellite laptop (cheap version) and a year long WiFi card from your favorite truck stop you're in range of a GPS system or under, and you have more options for killing time.
I was sitting in a Waffle House pk lot and playing a game, when a list of satelite sites came up. I was able to get on the unsecured site and sent a couple e-mails out. This was a pleasant surprise. I think the antenae was at a motel across the street.