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 163hp unit, while the other one gets its power and torque from a 4-cylinder, 16-valves 170hp 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. 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 that fact doesn't break the tie between the two cars. On the other hand, if we'd like to consider vehicle mass in this context too, which we definitely should, the Japanese car offers a considerable difference of 18% more metal.

I don't like generalizing things when it comes to reliability, although it does seem that Infiniti does have a slight advantage, when all the models are taken into account. That's the official data, while our visitors describe reliability of BMW with an average rating of 4.2, and models under the Infiniti badge with 4.5 out of 5. Independent research findings rank 3 Series as average reliability-wise, and Q50 is more or less at the same level.We should definitely mention that owners of cars with the same powertrain as the German car rank it on average as 4.7, while the one under the competitor's bonnet gets 4.5 out of 5.

BMW is a bit more agile, reaching 100km/h in 0.7 seconds less than its competitor. Still, it lacks the power to win the top speed competition, topping at 230 kilometers per hour, 1km/h less than the other car. When it comes to fuel economy things look pretty much the same for both cars, averaging around 4.3 liters of fuel per 100 kilometers (66 mpg), in combined cycle.

Infiniti 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, the Japanese car offers significantly better overall protection, taking the lead here. From there things take a different direction, with BMW offering somewhat better performance, just enough to call it quicker. To make things even better, it consumps less fuel! 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. 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™, out of 12.000+ vehicles we currently have in our database.