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 204hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 170hp 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. That aside, let's consider some other aspects which affect safety. 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, Boxster offers a marginal difference of 1% more metal.

Manufacturers have been building their reliability reputation for decades now and, generally speaking, it appears that BMW does have a slight advantage, when all the models are taken into account. These are the results of an independent reasearch, while our visitors describe reliability of Porsche with an average rating of 3.7, and models under the BMW badge with 4.2 out of 5. The same official information place Boxster as average reliability-wise, and Z3 is more or less at the same level.That apart, owners of different cars powered by the same engine as Boxster rank it on average as 3.0, while the one under the competitor's bonnet gets 4.4 out of 5.

Porsche is undoubtly more agile, reaching 100km/h in 1 seconds less than its competitor. In addition to that it accelerates all the way to 240 kilometers per hour, 16km/h more than the other car. When it comes to fuel economy the winner has to be BMW Z3, averaging around 9.2 liters of fuel per 100 kilometers (31 mpg), in combined cycle. We can't ignore that 16% difference compared to Boxster.

BMW 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 being considerably quicker, thus putting more smile on driver's face. It does come at a cost though, and that's the fuel consumption... I believe that, when we take all into account, we have only one winner here - the BMW. 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 thousands of similar, yet so different vehicles.