Five oversized function buttons located to the right of the display are used to power up the unit, enter the main-menu page, adjust volume settings, activate map zooming, and repeat spoken-voice prompts. An antenna is built into the top bezel, and there's a port on the rear for connecting an optional external antenna. Other connections include a USB port for hooking up to a PC (cable not included), a port for attaching a traffic receiver, and a 12-volt power jack. A 12-volt adapter and a traffic receiver are included in the box, along with an owner's manual and a traffic-receiver extender. You also get a telescoping suction-cup mount that lets you attach the unit to your windshield and share it with multiple vehicles. The mounting device is fairly sturdy, but because the unit is heavy, it's a good idea to position it so that the dashboard will help support its weight.The Cobra NavOne 4500 is loaded with all of the latest and greatest GPS features, including built-in street maps of the United States and Canada, voice- and text-guided driving directions in three languages, automatic routing, and speed alerts. You can view maps in 2D or 3D (bird's-eye) mode or get the lay of the land in terrain mode. Off-road enthusiasts will love the bread-crumb feature that leaves a dotted-line trail of areas traveled, making it easy to return to marked roadways. Along the top of the screen are status indicators that display your compass heading, your distance to and the direction of the next turn, the ETA to your destination, the map-zoom level, and the GPS signal strength.
Drivers can create routes using the POI database (there are more than 7 million of them) and the customizable address book, or they can enter city and street names via the onscreen keyboard. The NavOne 4500 is the first GPS system we've seen that actually calculates two routes and lets you compare them before selecting one, a great feature for travelers who may want to take in some local scenery along their journey. As with many of today's in-car GPS systems, you can choose to avoid toll roads or freeways and calculate routes based on fastest travel time or shortest distance. The unit will also recalculate your route if you decide to take a detour or wander off course. Other standard features include an odometer, a trip timer, a speedometer, and a compass.
The real-time traffic receiver is by far the coolest feature of the Cobra NavOne 4500. An included receiver picks up FM-radio signals from the Clear Channel radio network and overlays traffic conditions on to the map. With this information, you can view trouble areas, such as construction zones, slow-moving roadways, and other traffic incidents before you arrive on the scene. Affected roads are color-coded blue, and specific problem areas are flagged with icons, which, if you tap the screen, relays the cause of traffic in a small dialog box. As of this writing, the radio network is available in 48 major cities across the United States; a list of metro areas is available on Cobra's Web site, with more on the way. Our only gripe is that traffic notifications are limited to major roadways--interstates, freeways, and parkways--and do not include heavily traveled local highways and streets. Still, this feature can be a huge timesaver if you're heading into or out of a city such as New York or Los Angeles. Better yet, the 4500 warns you of upcoming delays and gives you the option of choosing one of two new routes that skirt the traffic zone, or you can take your chances and continue on your current route. Cobra gives you a free 90-day subscription to the traffic-information network when you purchase the NavOne 4500; after that, it'll cost you $59 a year for the service.The first time we powered up the Cobra NavOne 4500, we were impressed by how quickly it acquired a 3D fix (four satellites). It took just 35 seconds for the voice prompt to declare the unit ready to navigate. A quick glance at the GPS-status icon confirmed that we were locked and ready to go. Subsequent start-ups were also remarkably fast, thanks to Cobra's iASAP (Intelligent Accelerated Satellite Acquisition Protocol) technology.
Overall, the Cobra NavOne 4500 did a fine job of pinpointing our position on the map, but route calculations were a tad slower than we expected. Still, the routes were accurate, and we especially liked having the option to choose between two different routes. Voice-guided directions were also precise and clearly spoken. The real-time-traffic feature blew us away. As luck would have it, we hit a decent-size snowstorm during one of our road tests in Brooklyn, New York, and the NavOne 4500 warned us of several fender benders along the Belt Parkway. It even flagged spots on the road where fresh snow had fallen and offered to create a new route around the potentially hazardous areas. The true traffic test came when we ventured to the Long Island Expressway during the evening rush hour. Within minutes, the unit identified snarled traffic jams, as well as a construction site along the road leading into Manhattan's Midtown Tunnel. We selected a newly created route that took us out of the way but kept us moving the whole time, saving an estimated 30 to 45 minutes of bumper-to-bumper waiting time.