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 suv segment and utilize the same 5-door suv body style and the 4 x 4 wheel drive system, it all comes up to the specific petrol engine choice they offer. The first one has a BMW-engineered powertrain under the hood, a 6-cylinder, 24-valves 258hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 306hp engine designed by Mercedes Benz.

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. Moving further on, let's take a closer look at some additional safety-related facts. Both vehicles belong to the suv segment, which is generally a very good thing safety-wise, but that fact doesn't break the tie between the two cars. On the other hand, taking kerb weight as an important factor into account, GLK offers a marginal difference of 1% more metal.

Manufacturers have been building their reliability reputation for decades now and, generally speaking, it appears 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 with an average rating of 4.2, and models under the Mercedes Benz badge with 4.4 out of 5. Independent research findings rank X3 as average reliability-wise, and GLK is more or less at the same level.Above it all, drivers of cars with the same engine as BMW X3 rank it on average as 3.0, while the one under the competitor's bonnet gets 5.0 out of 5.

Mercedes Benz is a bit more agile, reaching 100km/h in 0.4 seconds less than its competitor. In addition to that it accelerates all the way to 238 kilometers per hour, 8km/h more than the other car. When it comes to fuel economy the winner has to be GLK, averaging around 8.1 liters of fuel per 100 kilometers (35 mpg), in combined cycle. We can't ignore that 11% difference compared to BMW X3.

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 slightly better overall protection and takes the lead. It all continues in the same direction, with Mercedes Benz offering somewhat better performance, just enough to call it quicker. 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 Mercedes Benz. 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.