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 'Executive car' segment, the only major difference here really is their wheel drive configuration (4 x 4 for the Audi and rear in the case of the Mercedes Benz). The first one has a Volkswagen-engineered powertrain under the hood, a 12-cylinder, 48-valves 450hp unit, while the other one gets its power and torque from a 12-cylinder, 48-valves 612hp engine designed by Mercedes Benz.

Unfortunatelly, neither of the two vehicles was submitted to the European New Car Assessment Programme (Euro NCAP) testing. This makes it virtually impossible for me to pick one over the other and I'm generally against buying such cars as the safety should really always come first. Still, apart from the official crash test results there are other things we need to be aware of. Both vehicles belong to the executive car segment, which is generally a fortune safety-wise, but that fact doesn't break the tie between the two cars. On the other hand, if we'd like to consider vehicle mass in this context too, which we definitely should, Mercedes Benz S offers a considerable difference of 11% 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, at least on all of the models level. These are the results of an independent reasearch, while our visitors describe reliability of Audi with an average rating of 4.2, and models under the Mercedes Benz badge with 4.4 out of 5. Independent research findings rank A8 as average reliability-wise, and S is more or less at the same level.That apart, owners of different cars powered by the same engine as Audi A8 rank it on average as 3.0 out of 5, exactly the same as the other one.

Mercedes Benz is a bit more agile, reaching 100km/h in 0.7 seconds less than its competitor. In addition to that it accelerates all the way to 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 14.8 liters of fuel per 100 kilometers (19 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, Mercedes Benz S offers significantly better overall protection, taking the lead here. It all continues in the same direction, with Mercedes Benz offering somewhat better performance, just enough to call it quicker. It does come at a cost though, and that's the fuel consumption... It's really tough to make a final decision here, but if I'd need to, I'd say Mercedes Benz. 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™, out of 12.000+ vehicles we currently have in our database.