I'm considering a Mercedes-Benz C-Class Estate. I've had a very brief test drive, but I'm struggling to get anything more than about 20 mins round the block. I accept that the dealership will seek to keep high performance vehicles to limited mileage and limited availability to 'time-wasters', but if I'm going to part with £70,000 it seems reasonable to expect a decent amount of time in the car. Any thoughts?