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 (front for the Audi and rear in the case of the BMW). The first one has a Volkswagen-engineered powertrain under the hood, a 4-cylinder, 16-valves 170hp unit, while the other one gets its power and torque from a 4-cylinder, 16-valves 177hp engine designed by BMW.

Both vehicles got tested by European New Car Assessment Programme (Euro NCAP), with the Audi 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, taking kerb weight as an important factor into account, Audi A6 offers a marginal difference of 5% more metal.

Reliability is not the best thing to consider on the make level, but it is worth mentioning 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, as well as BMW, with the same average rating of 4.2 out of 5. The same official information place 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 4.2, while the one under the competitor's bonnet gets 3.7 out of 5.

BMW is a bit more agile, reaching 100km/h in 0.6 seconds less than its competitor. In addition to that it accelerates all the way to 231 kilometers per hour, 6km/h more than the other car. When it comes to fuel economy the winner has to be 5 Series, averaging around 5.1 liters of fuel per 100 kilometers (55 mpg), in combined cycle. We can't ignore that 12% difference compared to Audi A6.

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 much better overall protection, which launches it ahead of the other contender. From there things take a different direction, with BMW offering somewhat better performance, just enough to call it quicker. To make things even better, it consumps less fuel! It's really tough to make a final decision here, but if I'd need to, I'd say 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™, among thousands of similar, yet so different vehicles.