Has anyone driven this in September and knows the best route and how long it takes?
According to viamichelin.com it should take just over 2 1/2 hours. I would guess a bit longer. You drive to the Autostrade north of Milan and then towards Gravollone Toce and over the Simplon Pass. It's a beautiful drive over the Alps. You can get precise directions on viamichelin.
One thing to bear in mind is that you will have to pay for an annual highway permit in Switzerland - I don't remember how much it is but more than $20 as I recall. And you'll need to change money.
But the drive is easy, if a bit twisty and congested in places.
Thank you so much! We'll do it!