Over the last year we've seen in-car GPS devices change into more than just navigational aides. High-end models now go above and beyond additional map coverage and in Garmin's Nuvi 660 we've found one of the most complete devices to date.

It certainly gets all the basics right. You'll find a superb 4.3-inch widescreen display making good use of large, colourful controls that mean it's easy to make changes and additions to your route on the move. Maps are especially clear and easily adjustable thanks to on-screen zoom controls, and built-in voice synthesis means that road names as well as directions are read out en-route.

The menu system is well designed, splitting your options into three simple categories to handle route planning, map browsing and control over a range of extras. There's 2GB of internal storage and preloaded maps of Western Europe as well as an expansion slot for increasing the capacity. Traffic reports and speed camera alerts work well alongside the navigation display, and you'll find Bluetooth built in to pair the device with your mobile for hands-free calling.

In addition to all of these features the Nuvi picks up points for the excellent array of extras it calls your 'travel kit'. In here you'll find an MP3 player, audio book reader, photo viewer and a range of travel aids such as a unit converter and world times. You can also browse travel guides to find out more about a chosen location and a language guide for quick translations on the move, although you'll need to purchase the full versions of these from the Garmin Web site at an additional cost.

The MP3 player in particular is impressive, working well alongside the map view, and is easily accessible at all times, avoiding the need to navigate around a string of menus to control your tunes. We've seen such additions in other GPS units in the past but few give you just the right amount of control and functionality you need to make it effective enough on the move.

Garmin has done a good job of placing all of the most commonly used menus within easy reach of the main map. A trip computer sits a single click away, along with a step-by-step waypoint view and access to the main menu and options to change the behaviour of the device or layout of the display. Voice prompts are clear and accurate, as is your position on the map when travelling.

It's also pretty slim and portable, with a well designed suction mount that takes up very little room on the dash. In short, the Nuvi 660 gets navigation just about spot on and in providing a host of easy-to-use extra features offers a lot for the money.

You can find the Nuvi 660 for around £350 online, which is about what you'd expect to pay for a high-end device. If you're looking for something that's easy to use, attractive and stylish, and with extras such as a travel kit and MP3 player, this would be an excellent choice in the current market.

There's a lot to choose from in the high-end GPS market but Garmin's Nuvi 660 offers that little bit extra over most rivals, in terms of both features and usability. It's one of the nicest in-car GPS units we've used and comes highly recommended for today's frequent traveller.