Well, these are two pretty similar cars we have here! It's only details that could potentially make the difference. Considering they both belong to the executive car segment and utilize the same 4-door sedan body style and the 4 x 4 wheel drive system, it all comes up to the specific diesel engine choice they offer. The first one has a BMW-engineered powertrain under the hood, a 6-cylinder, 24-valves 400hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 258hp engine designed by Audi.

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. That aside, let's consider some other aspects which affect safety. 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.

I don't like generalizing things when it comes to reliability, although it does seem that both brands display similar results in faults and breakdowns, all the models observed together. These are the official statistics, while our visitors describe reliability of BMW, as well as Audi, with the same average rating of 4.2 out of 5. Some independent research have also placed 7 Series as average reliability-wise, and A8 is more or less at the same level.That apart, owners of different cars powered by the same engine as 7 Series rank it on average as 5.0, while the one under the competitor's bonnet gets 3.0 out of 5.

BMW is undoubtly more agile, reaching 100km/h in 1.3 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 5.8 liters of fuel per 100 kilometers (49 mpg), in combined cycle.

BMW 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 this case though, it seems that both cars show similar levels of passenger protection all together, so that won't break a tie. But one thing that actually could is the performance, with BMW being considerably quicker, thus putting more smile on driver's face. To make things even better, it consumps less fuel! All together, there's not much more to say, in this case I wouldn't even consider anything but BMW. Anyway, that's the most objective conclusion I could've came up with and it's based solely on the information found on this website. Aspects such as design, practicality, brand value and driving experience are there for you to measure them out. Also, you could use the oportunity to find out which car, everything taken into account, would be the perfect choice for you in the eyes of the virtual adviser™, among more than 12.000 different ones in our database.