Do you use a GPS on holidays by bike

[Grahamm]

It was also useful in the twisties to be prepared for any bends that really tightened up, thus minimising any surprises.

I'm with you on this one.

Despite the (incorrect) implications by others that you're "staring at the Sat Nav all the time", it's no different from a mirror check, speedo check or lifesaver etc in that you don't do it at a critical point when you need your vision on the road ahead, but you do it as part of your visual scan.

I have my TomTom Rider set up for 2D rather than 3D map view since that gives you more view of what the road ahead might be doing *before* you get into the bend and find that it suddenly tightens on you.

Of course it's not a substitute for watching for Limit Point, visual clues such as telephone poles and so on as tommyardin points out, but it's another potentially useful piece of information which, used correctly, will be of benefit to you :thumbup