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 Mercedes Benz-engineered powertrain under the hood, a 8-cylinder, 32-valves 489hp unit, while the other one gets its power and torque from a 8-cylinder, 32-valves 530hp engine designed by BMW.

Unfortunatelly, neither of the two vehicles was submitted to the European New Car Assessment Programme (Euro NCAP) testing. This makes it virtually impossible for me to pick one over the other and I'm generally against buying such cars as the safety should really always come first. 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, but it doesn't do much to help us decide between the two. On the other hand, taking kerb weight as an important factor into account, BMW X7 offers a marginal difference of 2% 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. That's the official data, while our visitors describe reliability of Mercedes Benz with an average rating of 4.3, and models under the BMW badge with 4.1 out of 5. Unfortunatelly, I don't have enough insight that would allow me to comment in more details on the specific models level. Above it all, drivers of cars with the same engine as GLS rank it on average as 3.0 out of 5, exactly the same as the other one.

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 250 kilometers per hour, exactly the same as the other car does. When it comes to fuel economy an obvious choice would be GLS, averaging around 9.8 liters of fuel per 100 kilometers (29 mpg), in combined cycle. That's 32% difference compared to BMW X7!

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, BMW X7 offers slightly better overall protection and takes the lead. It all continues in the same direction, with BMW offering somewhat better performance, just enough to call it quicker. 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 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. Also, you could use the oportunity to find out which car, everything taken into account, would be the perfect choice for you in the eyes of the virtual adviser™, among thousands of similar, yet so different vehicles.