You're actually probably better off getting a decent phone cradle and using a smartphone with Waze, which is a free navigation phone app. It's usually better at getting you from A to B than a Garmin or TomTom and it costs nothing if you already have an iPhone or Android phone.

Still, if you want a sat nav, these are our top 10: www.honestjohn.co.uk/products/top-10s/top-10-sat-n.../