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 Porsche-engineered powertrain under the hood, a 6-cylinder, 24-valves 310hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 272hp engine designed by Mercedes Benz.

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. Moving further on, let's take a closer look at some additional safety-related facts. Both vehicles belong to the sports car segment, which is generally classifying them somewhere in the middle safety-wise, still it doesn't help us solve our dilemma, does it? Furthermore, taking kerb weight as an important factor into account, Boxster offers a marginal difference of 5% more metal.

I don't like generalizing things when it comes to reliability, although it does seem that Mercedes Benz does have a slight advantage, when all the models are taken into account. These are the official statistics, while our visitors describe reliability of Porsche with an average rating of 3.7, and models under the Mercedes Benz badge with 4.4 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 Boxster rank it on average as 3.0, while the one under the competitor's bonnet gets 5.0 out of 5.

Porsche 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 274 kilometers per hour, 24km/h more than the other car. When it comes to fuel economy the winner has to be Boxster, averaging around 9.8 liters of fuel per 100 kilometers (29 mpg), in combined cycle. We can't ignore that 8% difference compared to SLK.

Mercedes Benz is apparently more reliable, not too much, but just enough. 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, Boxster offers slightly better overall protection and takes the lead. It all continues in the same direction, with Porsche 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 Porsche. 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. 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™, out of 12.000+ vehicles we currently have in our database.