The sheer joy of driving on the French motorway system compared to the UK’s motorways makes the tolls seem worthwhile and once you get a “telepeage tag” makes life even easier! The route to Bourg St Maurice is,
Calais, Reims, Troyes, Dijon, I then go via Bourg en Bresse to Lyon airport, Chambery, Albertville. I do this route 3-4 time a year and usually reckon on 9 hours with a couple of stops.