Pricey Garmin and Magellan GPS navigators add features that may not be worth the cost

With more drivers turning to their smart phones for turn-by-turn directions, leading portable navigation device makers Garmin and Magellan are taking different routes in an effort to remain competitive. But our latest tests show that new top-of-the-line models from both brands offer no significant improvement to basic navigation functions nor are any easier to use than previously tested models. And, they don't come cheap.

Garmin sticks to the basics with the $350 Nuvi 3597LMTHD. This premium navigator builds on established Garmin strengths with a simple interface, quick response time, and crisp, high-resolution five-inch glass screen, all wrapped in a thin, slick package reminiscent of a smart phone.

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The biggest news is a new magnetic mount that makes installation and removal of the Garmin Nuvi 3597LMTHD a snap. Once the suction cup base is attached to the windshield, all you do is bring the unit close, and the magnet pulls it snugly into place. It's the easiest mounting system to use that we've experienced. Being virtually impossible to install it incorrectly, this clever mount is particularly helpful after dark.

But Garmin's new premium model lost some other useful features, including a pedestrian mode. Unless the slick style and handy mount are must haves for you, it's hard to justify its premium price.

Magellan has taken a different approach, loading their $250 SmartGPS with travel information and connectivity that goes way past simple guidance from point A to B. With access to Foursquare, Google search, and Yelp for anything else you might want to know on the road, the Magellan SmartGPS is meant to go head-to-head with smart-phone capability—without the phone part. Almost. It is WiFi capable, but on the road you'll normally be leveraging your phone's data plan to access those services through a Bluetooth connection, so be mindful of the limits of your data plan.

And all that information makes for a busy screen, with constantly changing pop ups offering restaurant suggestions, gas prices, and even discount coupons. Those graphics can be distracting and are so small that they're hard to read at a glance. They also take up a big chunk of the five-inch screen's real estate. Fortunately, a swipe of a finger can make them go away.