Satellite Navigation, Sony and Garmin systems tested

Sony and Garmin stage a navigational dance-off for your cash. Ignore the horror stories of roads turning into mud tracks, and in some cases not even existing at all: satnavs are terrific for getting to your final destination quickly and painlessly, whilst minimizing arguments with your partner.

Sporting a massive screen and Position Plus technology to help retain a signal in the face of disruptions, the NV-U82 is Sony's bid for motoring glory. The Garmin Nüvi 670 is a satnav/MP3/Bluetoorh combo equipped with FM transmitter. Can either knock TomTom off its navigational perch?

The Sony Nav-U NV-82 route calculation takes around 14 seconds. Voice instructions are clear and re-routing fast. The screen's big and uncluttered, with maps that even a blind man could follow.

With seven seconds, route calculation the Garmin Nüvi 670 dumps on the Sony's 14 seconds. Voice instructions of the Garmin Nuvi 670 are good, but the map appears cluttered and is harder to follow than the Sony's

The Sony's dedicated View and Voice/Position buttons are within easy reach of the touchscreen. Menus are very sophisticated, but this does mean more digging to change settings. The Garmin Nuvi 670 has no buttons which means all settings are reached via the 11-centimeter touchscreen. Large icons make it easier to use than the Sony and it's super fun to choose your car's own icon.

The Sony Nav-U NV-U82 has no Bluetooth, but the slightly bigger 12-centimeter screen is a jewel and there are heaps of POIs. You can even draw a route on-screen using Gesture Command. The Garmin Nuvi 670 has Bluetooth, 1.25GB memory, and integrated FM transmitter for voice instructions via your car stereo.

Our idea about this two satnav systems is that the Sony can't match the Garmin 670 for features or ease of use, but when it comes to main event, navigation, the outstanding screen and maps put the Sony ahead of the Garmin. The Garmin's combined fast operating with ease of use and loads of features for the Nuvi 670. It's not cheap, but if you want versatility, the Garmin Nuvi 670 is the box for you.