S line means big wheels and low profile tyres so worse ride quality, more expensive tyres and more likely to suffer pothole damage. Better an A6 SE on 16-inch wheels or a 5 Series SE on 17-inch (the minimum BMW size). Better the Audi V6 3.0 litre diesel or the BMW straight six 3.0 litre diesel than the 2.0 litre diesel engines which is subject to next years recall in the Audi and is under a voluntary recall for timing chain issues in the 5 Series.