Is a map easier than Sat Nav?

I have just driven two hours in the wrong direction whilst using sat nav in France!!! At least I paid attention and the below didn't happen to me!!



I grant you this is not a normal thing to do, drive two hours in the wrong direction but hey, I am in a country that is still foreign to me!! It happened when I was told "turn left in 200 metres" I duly did this, had no map on me and trusted it. Once you get on a motorway and it says "try and do a U turn" you are in trouble. The 'arrow' on my screen stated 60km to next junction..Great!!!

I am now asking the question, could you drive to a location using Sat Nav alone or do you need to have a map next to you? Do you trust Sat Nav entirely?

By this I mean, if you drove using Sat Nav and looked at no road signs, how often would you go in the wrong direction?

I sell GPS tracking (www.findyourfleet.com) for a living and this is a great product to locate somebody or your fleet but to get from A to B, does Sat Nav work??

I would love to hear any comments on this!