We're getting the Garmin software in this week.
Buy Garmin Mobile XT (European Maps)
Its a low cost alternative to tomtom. As Mike mentioned the McGuider software is very similar to tomtom.
Some of the all in one tomtom units we do don't cost much more than the software on its own though.
Refurbished TomTom - www.totalpda.co.uk Ltd.
Tomtom are focussing on the all in one units so at least you know updates are going to be available.