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 petrol engine choice they offer. The first one has a Toyota-engineered powertrain under the hood, a 4-cylinder, 16-valves 245hp unit, while the other one gets its power and torque from a 4-cylinder, 16-valves 211hp engine designed by Mercedes Benz.

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. 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, taking kerb weight as an important factor into account, Lexus IS offers a marginal difference of 7% more metal.

Reliability is not the best thing to consider on the make level, but it is worth mentioning that Lexus does have a slight advantage, at least on all of the models level. That's the official data, while our visitors describe reliability of Lexus with an average rating of 4.9, and models under the Infiniti badge with 4.5 out of 5. Unfortunatelly, I don't have enough insight that would allow me to comment in more details on the specific models level. We should definitely mention that owners of cars with the same powertrain as Lexus IS rank it on average as 5.0 out of 5, exactly the same as the other one.

Lexus 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 230 kilometers per hour, 15km/h less than the other car. When it comes to fuel economy the winner has to be Q50, averaging around 6.3 liters of fuel per 100 kilometers (45 mpg), in combined cycle. We can't ignore that 11% difference compared to Lexus IS.

Lexus 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, Lexus IS offers slightly better overall protection and takes the lead. It all continues in the same direction, with Lexus 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 Infiniti. 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. 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 more than 12.000 different ones in our database.