Horribly misleading headline. What's actually happening is that the Model S is outselling what they've decided is the roughly equivalent models from these companies, not that Tesla is selling more cars of all kinds. Still very good, which makes me wonder why they needed to exaggerate....
So I guess the difference lies in the more "affordable" models by Mercedes/BMW/Audi, like the Benz C class, BMW 1 and 3 series, and Audi A4. These are probably the best selling models for these companies, which makes this article even more senseless.
