FORTUNE — Last month, BMW and Mercedes Benz each released online-only commercials within 48 hours of one another. Both quickly went viral, but couldn’t have been more different. “The Catch” features the just-released Mercedes Benz SLS AMG Roadster, a Formula 1 driver, and a golf pro. The pro tees up, smacking drive after drive while the Roadster screams down a runway, trying to catch the ball. And eventually, it does, setting the Guinness world record for the “Farthest Golf Shot Caught in a Moving Car” in the process. Mercedes doesn’t disclose the amount it spends on individual ads, but the video is designed to feel inexpensive. The most expensive thing about it was probably the car, which goes for $277,000.

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“Bullet” depicts BMW’s M5 model as a rifle round fired into an open plain. The car smashes through a giant glass apple and three colossal, hanging water balloons before careening through a car-sized bulls eye. The ad is designed to transform the $90,000 M5 into a piece of “high performance art,” says Kevin Marcotte, Director of Marketing for BMW Canada. It is scored to classical music.

So which ad was more successful? BMW’s slickly produced video raked in over 1.3 million more YouTube views than the cost-effective Mercedes spot. According to Unruly Media’s Viral Video chart, BMW’s ad, “Bullet” has at 209,045 Facebook shares, more than three times the amount of the Mercedes ad. “Bullet” has been posted on 248 blog posts — double that of “The Catch.”