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 BMW-engineered powertrain under the hood, a 6-cylinder, 24-valves 340hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 265hp engine designed by Porsche.

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 that fact doesn't break the tie between the two cars. Furthermore, if we'd like to consider vehicle mass in this context too, which we definitely should, BMW Z4 offers a considerable difference of 13% more metal.

Reliability is not the best thing to consider on the make level, but it is worth mentioning that BMW does have a slight advantage, at least on all of the models level. That's the official data, while our visitors describe reliability of BMW with an average rating of 4.1, and models under the Porsche badge with 3.9 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 BMW Z4 rank it on average as 3.0 out of 5, exactly the same as the other one.

BMW 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 250 kilometers per hour, 14km/h less than the other car. When it comes to fuel economy things look pretty much the same for both cars, averaging around 8.7 liters of fuel per 100 kilometers (32 mpg), in combined cycle.

BMW 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 significantly better overall protection, taking the lead here. When it comes to performance, both vehicles provide similar experience, so I wouldn't point any of them out. Boxster still consumps less fuel, which needs to be taken into consideration. At the end, as much as I'd like to give you a winner here, it's simply a pure tie if you ask me. 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™, out of 12.000+ vehicles we currently have in our database.