More good news for consumers: Even as prices fall, the devices continue to pack more features into them. Two of the units we tested--the $210 Navigon 2200T and the $275 Garmin Nuvi 265T--include lifetime traffic service. That means that you don't have to purchase an extra-cost accessory or pay for a subscription service to avoid traffic tie-ups.

All of the devices we tested include text-to-speech functionality, which means that they pronounce street names for you. Instead of telling you to turn left in 500 feet, for example, the GPS unit will tell you to turn left in 500 feet onto Elm Street. Text-to-speech used to be a high-end feature, but it's become more common on lower-cost devices.

In most cases, though, the more you pay for a GPS, the more features you'll get. The chart-topping, $425 Magellan Maestro 4350 and the second-place, $480 TomTom GO 930 are the two most expensive systems we tested. And they do offer lots of extras such as hands-free calling with Bluetooth, FM transmission (so you can hear turns announced over your car stereo), and built-in audio and video players. But they also truly earned their leading positions due to their excellent navigation features: These two devices consistently found the quickest, most convenient routes.

The Navigon 2200T landed in our third spot, followed by the Garmin Nuvi 265T. Rounding out our Top 5 was the $220 TomTom One 130 S--a very basic, but still capable, navigator. All three of these devices will get you where you're going without a problem. They all sport 3.5-inch screens, which seems cramped compared to the 4.3-inch screens found on the Magellan and the TomTom GO 930. But they prove that you don't have to ante up the big bucks to get a reliable navigation device.

In fact, paying more doesn't mean you're necessarily going to get better navigation tool. The Sony NV-U94T, which missed the cut, lists for $400 (you can find it online for about $375)--and it provided some of the worst directions we've seen. In one case, its route was so far off that I was convinced I had entered the destination incorrectly (I hadn't). In another instance, I asked it to avoid toll roads, and it sent me on--you guessed it--a toll road.

If you want a GPS that will serve as a photo viewer, play back MP3s, and allow you to make hands-free phone calls, you shouldn't opt for a basic model. But if all you want is advice on how to get from point A to point B, you don't have to spend very much at all.