Sony isn't particularly well known in the Tom Tom-dominated satellite navigation (sat nav) market, but it does have a couple of devices out there.

The latest is the Sony NV-U50T. It's not the most compact of devices, but fits snugly into its cradle position with a reassuring clunk and, using the control wheels, it can be pointed in the direction of your choosing.

The NV-U50T comes complete with TMC traffic updates . In order to receive these, you'll need to connect the cars FM aerial to the sat nav holder. This will then have to be attached to your windscreen via the included suckers, creating a rather cluttered feel.

However, once up and running, it will warn you in advance if there's trouble ahead and reroute if necessary.

Planning a route is fairly simple, although for some reason Sony has decided not to include full eight-digit postcode support. You can put in the first four digits, but then it's up to you to pinpoint where you're planning to go by scrolling through the list of road names in that postcode region.

Considering how easy it is to use postcodes to navigate from one place to another, Sony is really missing a trick here.

It does include the UK, Republic of Ireland and partial France map coverage, though.

Navigating using the NV-U50T is reasonably straightforward. Thanks to the bright 3.5in display it's easy to glance at the screen and see where you are; a built-in sensor adjusts the brightness of the display according to the conditions.

The clear and uncluttered map screen updates reasonably smoothly while voice instructions tell which way to turn next.

If you stray off course, the NV-U50T immediately demands that you 'perform a u-turn'. It repeats this vocal instruction every few seconds until you give the handbrake a tug or it works out an alternative route.

The NV-U50T is a sturdy and well designed sat nav device. The TMC support is a bonus, but whether you'll actually be bothered to attach the FM aerial is up for debate.

Meanwhile, although you'll learn to live without full postcode support, it's something that Sony really should have included.

Also consider
TomTom One
Verdict: With good sound and a straightforward interface, the Tom Tom One is almost everything a navigation system should be
Rating: 4
Price: £280