[David]

A GPS unit will faithfully take you to the location that you enter even if it isn't your desired destination. You should always have a general idea of where you want to go and then let the GPS unit fill in the details. If you blindly go where it tells you to it may not be where you want to end up.

With a GPS unit, you always know where you are when you get lost.

Of the three main manufacturers of portable GPS units, Garmin, Magellan and Tom Tom, reviews that I have read list the Garmin routes as consistently good routes with Magellan a close second. Tom Tom is known for some pretty convoluted routes.

Each manufacturer has units at various price points, depending on the features.

Feature list:

Text to speech means that it doesn't say "turn right in .3 miles" it says "turn right on Main Street in .3 miles". This is particularly helpful when exiting a freeway on an exit that is very close to other exits.

Bluetooth support means that you can pair it with your cell phone and dial numbers using the GPS touch screen.

MP3 support means that you can listen to music or audio books stored on memory cards while you drive.

FM transmitter means that you can listen to the audio output from the GPS unit on your car's FM radio without having to connect a wire between the two. Older car radios, with cassette decks, can use a cassette adapter ($10-$15) to make the audio connection. The latest car radios have auxillary inputs that you can connect the GPS output to. Those car radios in between may only work with an FM transmitter.

Some of them support custom POIs (points of interest). With this feature you can use a web-based satellite image to identify the parking lot entrance closest to where you want to enter the gym. You take the latitude and longitude coordinates and enter them into a comma-delimited file that can be transferred to the GPS unit. When you just enter the school address, the GPS will guide you to the front of the school. In rural locations this isn't much of a problem but it can make a difference in larger cities during rush hour traffic.

The Garmin Nuvi 350, that includes text to speech, MP3 support and custom POI support can be purchased online for around $250. I have one of these that I am very happy with.