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 large family car segment and utilize the same 4-door sedan body style and the rear 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 510hp unit, while the other one gets its power and torque from a 4-cylinder, 16-valves 258hp engine designed by Mercedes Benz.

Both vehicles got tested by European New Car Assessment Programme (Euro NCAP), with the same number of safety stars gained in the process. 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 it doesn't do much to help us decide between the two. Furthermore, if we'd like to consider vehicle mass in this context too, which we definitely should, 3 Series offers a considerable difference of 13% 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. These are the official statistics, 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. Unfortunatelly, I don't have enough insight that would allow me to comment in more details on the specific models level. We should definitely mention that owners of cars with the same powertrain as 3 Series rank it on average as 3.0 out of 5, exactly the same as the other one.

BMW is undoubtly more agile, reaching 100km/h in 2.1 seconds less than its competitor. In addition to that it accelerates all the way to 290 kilometers per hour, 40km/h more than the other car. When it comes to fuel economy an obvious choice would be Mercedes Benz C, averaging around 7.1 liters of fuel per 100 kilometers (40 mpg), in combined cycle. That's 44% difference compared to 3 Series!

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, 3 Series offers significantly better overall protection, taking the lead here. It all continues in the same direction, with BMW 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. 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.