Me, I thought open debate involves everyone wehter or not they share my oppinion or yours for that matter!!"informative" I think everybody is trying to do that steve,it seems being corrected in the name of being informative is something you seem to have trouble with accepting.
Now on the subject of sat navs having problems and then its a good idea to have a map as back up, nice idea, good idea, but still it has its flaws. we have expensive very good scale truckers maps, and guess what, they have faults with some of their bridge heights being wrong, and in the wrong way too. old 52 through Grantham springs to mind the book says 13"6, and the bridge is actually 11"6" ! Its a fault in the 2007 and not corrected in the 2010 version!
So regardless of whether one is capable of reading a map or not,problems can still arise.
If we all followed your option, we would invest hundreds of hard earned in a gizmo that 3 months down the line is out of date as a road will of changed somewhere.
My option of buying this years map for a quid to check your gizmo is sending you along the right road is arguably the cheapest update available.
The rest of the contributers on this forum might have differing ideas on what navigation/mapping works for them.
I think that is called open minded debate and banter that is conducive to a resolution.
Perhaps you might agree on that point?
Steve L.