Two significantly similar cars, no doubt about that. Still, each one has something different to offer. Having both cars powered by diesel 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 (4 x 4 for the Audi and rear in the case of the BMW). The first one has a Volkswagen-engineered powertrain under the hood, a 6-cylinder, 24-valves 180hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 163hp engine designed by BMW.

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 BMW being a slightly better choice apparently. 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, but it doesn't do much to help us decide between the two. Furthermore, if we'd like to consider vehicle mass in this context too, which we definitely should, Audi A6 offers a marginal difference of 2% more metal.

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, at least on all of the models level. These are the official statistics, while our visitors describe reliability of Audi with an average rating of 4.2, and models under the BMW badge with 4.1 out of 5. Some independent research have also placed A6 as average reliability-wise, and 5 Series is more or less at the same level.We should definitely mention that owners of cars with the same powertrain as Audi A6 rank it on average as 3.5, while the one under the competitor's bonnet gets 5.0 out of 5.

Audi is a bit more agile, reaching 100km/h in 0.1 seconds less than its competitor. In addition to that it accelerates all the way to 223 kilometers per hour, 4km/h more than the other car. When it comes to fuel economy the winner has to be 5 Series, averaging around 6.7 liters of fuel per 100 kilometers (42 mpg), in combined cycle. We can't ignore that 18% difference compared to Audi A6.

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 my opinion, everything taken into account, 5 Series offers slightly better overall protection and takes the lead. From there things take a different 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 not difficult to say then that if I'd need to make a choice, it would definitely be the BMW. Nevertheless, let's not forget that people have different preferences and needs, so what really counts is your personal feel. I'm only here to help. 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.