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 diesel engine choice they offer. The first one has a FIAT-engineered powertrain under the hood, a 4-cylinder, 16-valves 170hp unit, while the other one gets its power and torque from a 4-cylinder, 16-valves 175hp engine designed by Mazda.

A starting point here would be to take a look at the results from European New Car Assessment Programme (Euro NCAP) tests which were performed on both of the cars, 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. Furthermore, taking kerb weight as an important factor into account, the German car offers a marginal difference of 8% more metal.

I don't like generalizing things when it comes to reliability, although it does seem that Mazda does have a slight advantage, at least on all of the models level. These are the official statistics, while our visitors describe reliability of Opel with an average rating of 4.2, and models under the Mazda badge with 4.4 out of 5. The same official information place Insignia as average reliability-wise, and 6 is more or less at the same level.That apart, owners of different cars powered by the same engine as the German car rank it on average as 4.6, while the one under the competitor's bonnet gets 4.5 out of 5.

Mazda is undoubtly more agile, reaching 100km/h in 1 seconds less than its competitor. Still, it lacks the power to win the top speed competition, topping at 216 kilometers per hour, 9km/h less than the other car. When it comes to fuel economy things look pretty much the same for both cars, averaging around 4.6 liters of fuel per 100 kilometers (62 mpg), in combined cycle.

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 slightly better overall protection and takes the lead. From there things take a different direction, with Mazda being considerably quicker, thus putting more smile on driver's face. 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 Opel. 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 more than 12.000 different ones in our database.