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 diesel engine choice they offer. The first one has a BMW-engineered powertrain under the hood, a 4-cylinder, 16-valves 150hp unit, while the other one gets its power and torque from a 4-cylinder, 16-valves 150hp 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. Still, apart from the official crash test results there are other things we need to be aware of. 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. On the other hand, taking kerb weight as an important factor into account, Mercedes Benz C offers a marginal difference of 4% 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. Independent research findings rank 3 Series as average reliability-wise, and C is more or less at the same level.That apart, owners of different cars powered by the same engine as 3 Series rank it on average as 5.0, while the one under the competitor's bonnet gets 3.0 out of 5.

Mercedes Benz is a bit more agile, reaching 100km/h in 0.3 seconds less than its competitor. Still, it lacks the power to win the top speed competition, topping at 222 kilometers per hour, 4km/h less than the other car. When it comes to fuel economy things look pretty much the same for both cars, averaging around 4.4 liters of fuel per 100 kilometers (65 mpg), in combined cycle.

BMW 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, Mercedes Benz C 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. It does come at a cost though, and that's the fuel consumption... It's really tough to make a final decision here, but if I'd need to, I'd say BMW. 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. 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.