Not just Tom Tom, I had a VDO Dayton that tried that as well but I stopped when the tarmac did, my wife also went to an area meeting many years ago using a Road Angel sat nav that tried to send them over a Golf Course to the venue.
don't think groundsmen would have been to impressed!
Not a fan of them myself, useful sometimes but not always, and does not always pick the best route, can't beat an atlas, plus I found myself becoming reliant on it and you stop looking at road signs and concetrate on this little box on the dash instead. Good for getting you out of towns and cities, and back home when lost but that is about it, I did use my old VDO in Sicily last year and it worked fairly well, so can be useful. after all it is only a navigation aid.
My Meg has onboard Sat Nav the red arrow thing which is quite useful but does not do postcodes just road names so you need multi map first to find a near road name, its distance is fairly accurate and does not often send you wrong. would be nice if it gave you an arrival time and total distance, which most sat navs do I find that the best bit of info from them really, mine just tells of distance to next change of direction.
used properly they are ok, nothing better than the human brain though!
