Tbh Im not sure how much use the vehicle size facility is. Its rare indeed on a journey that you will find your caravan too high and roads with weight and width limit are usually clearly marked. The entrances and access lanes to some campsites are often very narrow but are always passable with care.
With this in mind my wifes car has the Garmin unit fitted with free live updates, speed cam database and also importantly a dashcam built in which is excellent. Throw in hands free and voice command and it all adds up to a highly efficient unit. It also warns of traffic issues and dangerous situations like severe bends.
Hard to agree with that. Try doing a comparison with the same start and end destination with caravan route turned on and off. I have with TomTom and Via Michelin. Then examine the roads it is avoiding. The make sens.
I used my TomTom camper (before it gave up the ghost), successfully. But when it had to be rebooted, it lost the settings I had entered for height and weight and length.
This is what it tried to take me through in deepest France:
At first I was not bothered as I was following a lorry. But then he peeled off to the left. Next I am desperately grieving to think if 2.6 m is enough. Then I saw the estate road on the right, I am pleased to say. Loads of traffic behind me. It all happened very fast.
I then had a 20 mile diversion to get to the other side of the railway line.
Of course there are methods of pre-planning routes. But personally, I like an easy life.
John