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 5-door suv body style within the same 'SUV' 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 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 Volkswagen.

The first thing to look into here would be the results from European New Car Assessment Programme (Euro NCAP) tests performed on the two cars. Good thing is that both vehicles got tested, with the same number of safety stars gained in the process. Still, apart from the official crash test results there are other things we need to be aware of. Both vehicles belong to the suv segment, which is generally a very good thing safety-wise, still it doesn't help us solve our dilemma, does it? Furthermore, if we'd like to consider vehicle mass in this context too, which we definitely should, GLK offers a considerable difference of 11% 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, when all the models are taken into account. These are the official statistics, while our visitors describe reliability of Mercedes Benz with an average rating of 4.3, and models under the Audi badge with 4.2 out of 5. Some independent research have also placed GLK as average reliability-wise, and Q3 is more or less at the same level.That apart, owners of different cars powered by the same engine as GLK rank it on average as 4.6, while the one under the competitor's bonnet gets 3.9 out of 5.

Audi is a bit more agile, reaching 100km/h in 0.3 seconds less than its competitor. In addition to that it accelerates all the way to 212 kilometers per hour, 7km/h more than the other car. 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.

Mercedes Benz 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, GLK offers significantly better overall protection, taking the lead here. 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... No mistake, whatever you decide here, but I'd still go for the Mercedes Benz. 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 thousands of similar, yet so different vehicles.