There was a time when Tomtom devices had a captive market as far as satellite navigation was concerned, despite them being priced a little higher than its competitors.

A few years back only Tomtom could offer the balance of accuracy and ease of use required by the average road user. Now the company is facing quality competition from Garmin and Navman, among others, while the likes of Medion and Packard Bell produce devices that offer decent value around the £100 mark. Clearly Tomtom has seen that it is time to add more value, and the One XL is a fair start, despite being £30 dearer than its predecessor, the Tomtom One.

The XL's main selling point is the wide screen, a 4.3in colour one, which, as with earlier models, is touch-sensitive so there's no fiddling with buttons to access menus and options. The device is now much thinner than previous models – barely the depth of a cigarette packet.

The extra screen width made a real difference on the route we used to test the XL, in the Scottish highlands. The roads at the periphery of the main route were clearer, giving a better context for the spoken directions (which were as clear as ever, although only one voice style – a British female – is provided). The onscreen keyboard is still fiddly for adult fingers so it's worth keeping a pen with a lid in the glove box, for easier use.

TomTom has introduced a new menu screen for navigation that improves vastly on earlier versions: instead of just choosing an address or point of interest, drivers are now given the choice of entering a postcode, house and street number or just general directions to a city centre, as well as choosing to drive to the crossing point between two roads.

The wider screen means you can also see more of long road names when entering post codes, although particularly long names can still leave you wondering whether you have found the street, road, avenue or lane, as this bit drops off the side of the screen.

The windscreen attachment doesn't look or feel as sturdy as its predecessors, but it took the bumpy mountain roads of the highlands in its stride, and directions were accurate, despite the tendency of all sat-navs to take drivers via main roads wherever possible. The One XL offers all of the customary sat-nav features such as the ability to store favourites, locate points of interest and plot routes via other addresses. An in-car charger is provided, although an AC version is not.

Also included are maps for all of western Europe and a pre-installed record of speed camera locations, although only fixed cameras (not mobile ones) are stored. If you want to pay extra, it's possible to download features such as additional voices, scenic routes and travel information.

If you have a phone with Bluetooth, you can even do this while out and about. Software is included to copy updates to the device, and this gives you the chance to back up recent and favourite routes or addresses.

In all, though, the key element is price. The One XL is a very competent navigation aid, and at a suggested retail price of £279 it's still expensive compared with some. But for what it does and how it does it, £279 is good value, particularly as it's likely to be cheaper online.