M3 in the Alps
I've driven the French Alps a couple of times in the M3...in fact, just came back from skiing near the Italian border (Dunlop M3 winter tires worked great in the cold/ice, no snow, so didn't even need the backup snow chains). There are great roads and wonderful switchbacks (which in winter become some excellent ski runs...funny to hit the same apex on a pair of skis). The DCT is fantastic for those brief straights where you need to pass 2-3 slow moving cars/vans in a single leap.
If you have passenger, make sure to bring motion sickness tablets. You and they will enjoy the drive more that way!