I'm bound from the Eurotunnel to Evenos St Anne, and then from Evenos to Litteau (near St Lo.) this summer, around 1,500 miles and GULP €350 in tolls. Now I really like the French autoroutes but that's half my drinking money for the fortnight...

I'm driving at night, solo, and with a pretty good SatNav. Would off the beaten track be a better bet, or would I just lose so much time (anything plus 5 hours is a drag) and burn more fuel that it would be self defeating?
Any suggestions?
