[7952]

Getting sent 1km or even 100m away by accident could be critical depending on the geography. The closeness of the numbers increases that possibility. And an error that reports Vietnam is easy to coorrect.

[oneeyedpigeon]

Easy to recognise. I'm not sure the emergency services having to play a process-of-elimination word game is 'easy to correct'.

[7952]

The app I have used makes it very clear. It autocompletes options as you type with a little flag. It is worth trying out if you have never used it.