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 sports car segment and utilize the same 2-door cabriolet 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 Mercedes Benz-engineered powertrain under the hood, a 6-cylinder, 24-valves 306hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 306hp engine designed by BMW.

Unfortunatelly, neither of the two vehicles was submitted to the European New Car Assessment Programme (Euro NCAP) testing. This makes it virtually impossible for me to pick one over the other and I'm generally against buying such cars as the safety should really always come first. Still, apart from the official crash test results there are other things we need to be aware of. Both vehicles belong to the sports car segment, which is generally classifying them somewhere in the middle safety-wise, but it doesn't do much to help us decide between the two. On the other hand, if we'd like to consider vehicle mass in this context too, which we definitely should, BMW Z4 offers a marginal difference of 3% more metal.

I don't like generalizing things when it comes to reliability, although it does seem that both brands display similar results in faults and breakdowns, all the models observed together. These are the results of an independent reasearch, while our visitors describe reliability of Mercedes Benz with an average rating of 4.4, and models under the BMW 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. We should definitely mention that owners of cars with the same powertrain as SLK rank it on average as 5.0, while the one under the competitor's bonnet gets 4.0 out of 5.

BMW is a bit more agile, reaching 100km/h in 0.4 seconds less than its competitor. In addition to that it accelerates all the way to 250 kilometers per hour, exactly the same as the other car does. When it comes to fuel economy an obvious choice would be SLK, averaging around 7.1 liters of fuel per 100 kilometers (40 mpg), in combined cycle. That's 32% difference compared to BMW Z4!

Mercedes Benz 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, BMW Z4 offers slightly better overall protection and takes the lead. It all continues in the same direction, with BMW 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 not difficult to say then that if I'd need to make a choice, it would definitely be the Mercedes Benz. Anyway, that's the most objective conclusion I could've came up with and it's based solely on the information found on this website. Aspects such as design, practicality, brand value and driving experience are there for you to measure them out. 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.