Two significantly similar cars, no doubt about that. Still, each one has something different to offer. Having both cars powered by diesel engines and utilizing the 5-door hatchback body style within the same 'Large family car' segment, the only major difference here really is their wheel drive configuration (rear for the BMW and front in the case of the Opel). 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 4-cylinder, 16-valves 170hp engine designed by FIAT.

Both vehicles got tested by European New Car Assessment Programme (Euro NCAP), 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 large family car segment, which is generally a good thing safety-wise, but that fact doesn't break the tie between the two cars. Furthermore, when it comes to weight, a factor that most people underestimate, 4 Series Gran Coupe offers a marginal difference of 7% more metal.

Manufacturers have been building their reliability reputation for decades now and, generally speaking, it appears that Opel does have a slight advantage, all the models observed together. These are the results of an independent reasearch, while our visitors describe reliability of BMW with an average rating of 4.1, and models under the Opel badge with 4.2 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 4 Series Gran Coupe rank it on average as 4.8, while the one under the competitor's bonnet gets 4.7 out of 5.

BMW is way more agile, reaching 100km/h in 3.1 seconds less than its competitor. In addition to that it accelerates all the way to 250 kilometers per hour, 24km/h more than the other car. When it comes to fuel economy things look pretty much the same for both cars, averaging around 5.3 liters of fuel per 100 kilometers (54 mpg), in combined cycle.

Opel 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, 4 Series Gran Coupe offers slightly better overall protection and takes the lead. It all continues in the same direction, with BMW outracing its opponent in any situation possible, making it better choice for boy racers. 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 BMW. 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.