Prices for Global Positioning System navigators are dropping, and features such as internal batteries, touch screens, preloaded map databases, MP3 players, and spoken street names ("Turn left on Maple Street," not just "Turn left") are trickling down from pricey models to lower-cost ones. Real-time traffic alerts can also be had from less expensive GPS units, but expect to pay a subscription fee.

We tested 18 devices costing from $250 to $700. All were very good or excellent at letting you enter a destination, but they differ in other respects, such as screen size, the controls' convenience, the information given to the driver, the ability to go into biking or walking mode, and the ability to offer detours or limit route options--to avoid toll roads, for instance.

Full of features. The top five devices in our Ratings (available to ConsumerReports.org subscribers only) are multitalented. All provide top-notch navigation functions, including street-name pronunciation. All can report traffic delays, but one model must be paired with a compatible Bluetooth phone to do so; with two others, you need to buy a traffic receiver. All include an MP3 player. Three units also include Bluetooth hands-free calling, which lets you make and receive calls through the unit's internal speaker, with access to your phone book and call history. One navigator includes modes for hiking and marine navigation.

CR Best Buys. Several units are strictly navigators, but they do that job well and are especially easy to use. Another navigator is very compact yet has a 3.4-inch screen and provides traffic updates with a compatible Bluetooth phone.

CR's take. You can buy a capable navigator for $300 or less; more money brings niceties such as hands-free Bluetooth calling. Bear in mind that although any of these systems will usually get you where you need to go, we found minor errors on most maps. There's no substitute for local knowledge.