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 front wheel drive system, it all comes up to the specific petrol engine choice they offer. The first one has a Mazda-engineered powertrain under the hood, a 4-cylinder, 16-valves 120hp unit, while the other one gets its power and torque from a 4-cylinder, 16-valves 140hp engine designed by Opel.

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, still it doesn't help us solve our dilemma, does it? On the other hand, taking kerb weight as an important factor into account, the German car offers a considerable difference of 16% more metal.

Reliability is not the best thing to consider on the make level, but it is worth mentioning that Mazda does have a slight advantage, at least on all of the models level. That's the official data, while our visitors describe reliability of Mazda with an average rating of 4.4, and models under the Opel badge with 4.2 out of 5. Independent research findings rank 6 as average reliability-wise, and Insignia is more or less at the same level.That apart, owners of different cars powered by the same engine as the Japanese car rank it on average as 5.0, while the one under the competitor's bonnet gets 4.5 out of 5.

Opel is a bit more agile, reaching 100km/h in 0.5 seconds less than its competitor. In addition to that it accelerates all the way to 207 kilometers per hour, 11km/h more than the other car. When it comes to fuel economy the winner has to be the German car, averaging around 5.7 liters of fuel per 100 kilometers (50 mpg), in combined cycle. We can't ignore that 12% difference compared to the Japanese car.

Mazda 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 German car offers significantly better overall protection, taking the lead here. It all continues in the same direction, with Opel offering somewhat better performance, just enough to call it quicker. To make things even better, it consumps less fuel! All together, there's not much more to say, in this case I wouldn't even consider anything but Opel. 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. I suggest you spend two more minutes in order to find out which car, based on your needs and budget, would be picked by the virtual adviser™, among thousands of similar, yet so different vehicles.