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 (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 279hp unit, while the other one gets its power and torque from a 8-cylinder, 40-valves 335hp engine designed by Volkswagen.

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. Moving further on, let's take a closer look at some additional safety-related facts. Both vehicles belong to the executive car segment, which is generally a fortune safety-wise, but it doesn't do much to help us decide between the two. On the other hand, if we'd like to consider vehicle mass in this context too, which we definitely should, Audi A8 offers a marginal difference of 1% 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 official statistics, while our visitors describe reliability of Mercedes Benz with an average rating of 4.4, and models under the Audi badge with 4.2 out of 5. The same official information place S as average reliability-wise, and A8 is more or less at the same level.Above it all, drivers of cars with the same engine as Mercedes Benz S rank it on average as 3.0 out of 5, exactly the same as the other one.

Audi is undoubtly more agile, reaching 100km/h in 1 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 11.7 liters of fuel per 100 kilometers (24 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 A8 offers slightly better overall protection and takes the lead. It all continues in the same direction, with Audi being considerably quicker, thus putting more smile on driver's face. 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 Audi. 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 more than 12.000 different ones in our database.