The dealership is excellent and does its best, but my car had a battery drain problem that left me stranded in airport parking lots several times after long trips from Europe and Asia. After many interventions and, as long as a week at the dealership at a time, to check it out, they changed the battery. I suspect once the battery gets old it will discharge again but I only have a few months left on the lease. The car also has had small problems that should not appear on a 55K plus car.
Diesel engine overall comfort.
Better navigation system. I use a Tom Tom because the one that they supply with the car is a terrible system. Include a bluetooth system for cell phones with the car. I purchased ($400!!!)the one that is suggested and it broke after about a year. Now I use the blutooth on my Tom Tom navigator.