| Thanks for the welcome Addman.
Yes you are right that it does involve an ongoing subscription. However, you can pay as you go or take out an annual or 'lifetime' subscription.
The annual sub is £10 per month which is ovbiously £120 per year. However, it is good value as it is regularly updated so no new software to buy. I read somewhere that 15-20 per cent of the UK road network changes in some way every year so to keep up to date would need a new mapping disc. I am not sure how much this is but have been advised it is about £150 for a DVD so smartnav is quite good value. | 
