London to Turin then Udine and back - route question

[tgr]

I am thinking of driving down to Turin (through France on the motorway for speed) and from there to Udine using the A4.

The only question I have is whether to return the way I came, or go up through Austria and diagonally across Germany via Munich.

Any thoughts/experience on which is better?

Putative date for this is November some time

Edited to add: I'm not interested in 'good driving roads' as I don't have much time and just want the right compromise between speed and comfort, therefore it will be all motorway

Edited by tgr on Tuesday 2nd September 11:21

[tgr]