The TomTom XL satellite navigation device may have an oversized 4.3in touchscreen, but the overall design is anything but extra large.

The XL is the first of a new breed of TomTom devices that sports a slimmed down cradle unit. For drivers fed up with the chunky cradles and curved armatures that usually accompany satnav units, the TomTom XL's new EasyPort mount design will be great news.

The TomTom XL twists in and out of the circular retaining bracket and can be angled forward as far as you need so the screen is clearly visible to the driver.

The whole setup of the TomTom XL feels secure and more robust - we managed to snap the top off the brittle stalk on a TomTom device we tested a year or so ago. The new design was therefore a reassuring development.

The satnav unit itself has also been transformed from the squat, boxy design for which TomTom originally became known. The TomTom XL has undergone a change of shape similar to and almost as dramatic as the change from a bulky CRT TV screen to a dainty flatpanel. Again, losing the bloat makes the unit seem far more attractive.

One of the most important innovations in the TomTom annals was 2007's introduction of a feature known as MapShare. This allows TomTom owners to note and mark alterations to the mapped route - ongoing roadworks, a new road or a thoroughfare that has now been pedestrianised or access blocked off at one end. These can then be shared via TomTom's web portal, TomTom Home. TomTom verifies the accuracy of these user-submitted edits before making them publicly available.

By regularly logging on to the TomTom web portal and installing the latest map updates, users can be sure they've always got the most up to date and accurate maps. It does TomTom no harm in a marketing sense either, since the company can then claim that products such as the TomTom XL have maps that are more up to date than any other satnav company's.

Now map data provider TeleAtlas has formally become a subsidiary company of TomTom, we imagine TomTom will always have the freshest maps ahead of other vendors.

A addition to this year's satnav models is the IQ Routes feature. This collates actual traffic data from TomTom users and other regular road users and uses it to work out exactly how fast traffic is able to travel along a given road at a particular time of the day.

When we first tried out this concept in the back roads of rural Kent, we were less than convinced. Six months later, however, and with the addition of thousands, if not millions, of road hours to the TomTom data banks, this feature works very effectively indeed.

Intelligent laning information verbally delivers instructions about which part of the road you should be on when you approach a junction and this is reinforced by the path you need to steer being clearly marked in a darker blue on the TomTom's maps.

We tested the TomTom XL up and down the country and on various routes through and around the capital, and found it uncannily accurate.

TomTom has just announced that it is extending this time-based routing feature on yet another new range of satnav devices, so you should be given the most appropriate advice about the route to take depending on the five-minute slot before you depart. Let's hope it takes into account the extra 20 minutes required to repack the boot and to dash upstairs for that vital item you've left on the bed.

If you're plotting a journey coming from the west of London and need to end up somewhere in the suburbs to the east or south-east, knowing whether it's faster to use the London Orbital road, the south circular or head straight through the centre, such time-based advice is incredibly helpful. Even in the depths of rush hour, going straight seemed to work best and having a dependable satnav such as the TomTom XL to help us negotiate unfamiliar back streets and shortcuts helped keep the stress to a minimum.

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