mapping is also very out of date , it doesn't even have my home address in the UK , and the road was built nine years ago !!!!
I would advice you to check http://www.navigon.com/site/uk/en/service_support/mapreporting to check address before you spend a small fortune on this !
To be fair you'll find different inaccuracies in all satnav products. Even in central London the latest TomTom map I use still sees roundabouts that were removed years ago, and in deepest Sussex is convinced there's a handy turning off the A27 where there never has been (and that road is very very old).
You are unlikely to find a product that is wholly accurate, just differently inaccurate.