This is how it is explained in the media manual
After starting route guidance, three alternative
routes will be suggested depending on
the selected setup ››› Fig. 31. These 3 routes
correspond to the selectable route options:
Economical, Fast and Short.
Route criteria: Meaning
Blue route: Economical route, the route is calculated by
taking into consideration economic factors.
Red route: Fastest route to the destination, even if it is
necessary to make a deviation.
Orange route: Shortest route to the destination, even if it
results in longer travelling time. The route may have unconventional
sections such as secondary roads.
I have found that the Blue seems to be the best routing option.
I found on holiday, the the Red and the Orange routes tried to take me down some unmade lane.
Some of them the it was just for a 4X4, the car never would have got through.
Personally my TomTom is far far better that the factory system.
Routing and guidance is far superior, and the lane guide on the Tom Tom is Fantastic.
I am trying to give this Factory system a good chance, and see how it fairs when I go over to Germany at the end of September.
But I will be taking the Tom Tom just in case. As I trust that.
Also the Tom Tom has Speed Camera Warnings which is great when you are in a different country, and they are not bright Yellow like ours. where as the Factory system does not have this.
So maybe looking to get a permanent mounting for my Tom Tom.. LOL
Which