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 5-door wagon body style within the same 'Large family car' segment, the only major difference here really is their wheel drive configuration (rear for the BMW and front in the case of the Audi). The first one has a BMW-engineered powertrain under the hood, a 6-cylinder, 24-valves 150hp unit, while the other one gets its power and torque from a 4-cylinder, 20-valves 150hp engine designed by Audi.

Both vehicles got tested by European New Car Assessment Programme (Euro NCAP), 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 large family car segment, which is generally a good thing safety-wise, but that fact doesn't break the tie between the two cars. Furthermore, taking kerb weight as an important factor into account, 3 Series offers a considerable difference of 12% 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. That's the official data, while our visitors describe reliability of BMW, as well as Audi, with the same average rating of 4.2 out of 5. The same official information place 3 Series as average reliability-wise, and A4 is more or less at the same level.We should definitely mention that owners of cars with the same powertrain as 3 Series rank it on average as 3.0, while the one under the competitor's bonnet gets 4.5 out of 5.

Audi is undoubtly more agile, reaching 100km/h in 1.7 seconds less than its competitor. In addition to that it accelerates all the way to 218 kilometers per hour, 4km/h more than the other car. When it comes to fuel economy the winner has to be Audi A4, averaging around 7.9 liters of fuel per 100 kilometers (36 mpg), in combined cycle. We can't ignore that 14% difference compared to 3 Series.

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, 3 Series beats the other contender by far, making it the best choice without even considering other things. From there things take a different direction, with Audi being considerably quicker, thus putting more smile on driver's face. To make things even better, it consumps less fuel! I believe that, when we take all into account, we have only one winner here - the Audi. 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. I suggest you spend two more minutes in order to find out which car, based on your needs and budget, would be picked by the virtual adviser™, among thousands of similar, yet so different vehicles.