Two significantly similar cars, no doubt about that. Still, each one has something different to offer. Having both cars powered by petrol engines and utilizing the 4-door sedan body style within the same 'Luxury car' segment, the only major difference here really is their wheel drive configuration (rear for the Mercedes Benz and 4 x 4 in the case of the Audi). The first one has a Mercedes Benz-engineered powertrain under the hood, a 8-cylinder, 24-valves 476hp unit, while the other one gets its power and torque from a 10-cylinder, 40-valves 435hp engine designed by Volkswagen.

A starting point here would be to take a look at the results from European New Car Assessment Programme (Euro NCAP) tests which were performed on both of the cars, with the same number of safety stars gained in the process. That aside, let's consider some other aspects which affect safety. Both vehicles belong to the luxury car segment, which is generally a very good thing safety-wise, still it doesn't help us solve our dilemma, does it? On the other hand, if we'd like to consider vehicle mass in this context too, which we definitely should, Audi A6 offers a considerable difference of 10% more metal.

Manufacturers have been building their reliability reputation for decades now and, generally speaking, it appears that both brands display similar results in faults and breakdowns, when all the models are taken into account. These are the official statistics, while our visitors describe reliability of Mercedes Benz with an average rating of 4.3, and models under the Audi badge with 4.2 out of 5. Independent research findings rank E as average reliability-wise, and A6 is more or less at the same level.We should definitely mention that owners of cars with the same powertrain as Mercedes Benz E rank it on average as 3.0, while the one under the competitor's bonnet gets 4.0 out of 5.

Mercedes Benz is a bit more agile, reaching 100km/h in 0.5 seconds less than its competitor. Still, it lacks the power to win the top speed competition, topping at 250 kilometers per hour, exactly the same as the other car does. When it comes to fuel economy things look pretty much the same for both cars, averaging around 13.2 liters of fuel per 100 kilometers (21 mpg), in combined cycle.

Audi appears just a bit more reliable, although the difference is truly marginal. The most important thing when deciding between any two vehicles should always be safety, both passive and active. In my opinion, everything taken into account, Audi A6 offers significantly better overall protection, taking the lead here. From there things take a different direction, with Mercedes Benz offering somewhat better performance, just enough to call it quicker. To make things even better, it consumps less fuel! At the end, as much as I'd like to give you a winner here, it's simply a pure tie if you ask me. In any case that's my personal view, built upon all the data available to me. What should decide here though is the way you feel about the two vehicles, and I hope you'll find my guidelines useful in the process. In case you have two minutes to spare I invite you to define your needs, desires and budget and see which car would be chosen by the virtual adviser™, among thousands of similar, yet so different vehicles.