What are the most significant differences between the Audi A6 and the Audi S6?

I have been considering purchasing either an Audi A6 or an Audi S6, but I am unsure of the key differences between the two models. Can someone provide a detailed comparison between these two vehicles?

The Audi S6 boasts a more powerful engine, with a V8 producing 444 horsepower compared to the A6's V6 with 335 horsepower. This results in a quicker acceleration and sportier driving experience.

While the A6 offers standard all-wheel drive, the S6 comes with Audi's advanced Quattro system, providing improved handling and traction in all weather conditions.

In terms of exterior design, the Audi S6 has a bolder, more aggressive look with features such as a sport-tuned suspension and larger wheels. The A6 has a sleeker, more understated design.