Even though BMW claims that the new 8 Series is not necessarily a rival for the S-Class Coupe model from Mercedes-Benz, some journalists see the two competing on some levels. The S-Class is bigger and definitely more comfortable, but that’s what buyers of that car are looking for. Go for the AMG model and things change a bit, just as they will once the full-on BMW M8 comes out. In the meantime though, we have to make due with the M Performance model, the M850i.

That’s not a bad choice though and it’s a pretty competent car by all known metrics. It has more than enough power and a really enticing sound, among many other things. The M8 will take everything up to a whole new level, but until we get to see it, reviewers around the world will use the M850i xDrive against anything they can get their hands on, including an S63 AMG Coupe, as is the case in the video posted below.

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The footage is rather long at over 30 minutes and it’s in Russian, but it does include a number of very interesting tests. The M850i is not exactly on par with the AMG S63 but that didn’t stop the reviewers from pitting the two against each other both from standstill and from 50 km/h. And while the spec sheet says that the 530 HP and 750 Nm of the M850i shouldn’t be a close match to the 585 HP and 900 Nm of the Mercedes, real-life results show otherwise.

The BMW won every single race, lest the ones where the Mercedes driver launched too soon. From standstill, the BMW simply walked away from the S63, even when the AMG driver launched early. It was a very interesting display of power. That’s why the guys took the M Performance model to the dyno to see how much power it really makes. The end result showed some 470 HP at the wheels which, according to their math – including an 18% transmission loss – translates into some 570 HP at the crank.

The action starts at the 16-minute mark.