What would you do if someone handed you the keys to the world's fastest SUV? If you were in Copenhagen, Denmark, you'd do what we did on a recent trip: Take the 607-horsepower Kleemann ML55K out for a spin.

It was with some degree of hesitation that we put the pedal to the metal on a few selected Danish highways in the exact same Kleemann ML55K that the 2002 Danish touring-car champion Jason Watt used to set the world's SUV top-speed record last February at the Nardo test track in Italy (see sidebar).

Even knowing that, nothing could have prepared us for the sheer sensation of acceleration on tap with the ML55K. While cruising at 120 kph (about 70 mph), the first time we mashed the pedal, we got near-instant acceleration, which doubled our speed to more than 230 kph (142 mph). This is in what remains a truck and at 5300 pounds is no lightweight. When you think about it, the team at Kleemann built an SUV that nearly defies the laws of physics.

While we had no desire to push the ML55K to the upper reaches of its considerable limits, we did want to experience one certified blast over 150 mph, which meant the kilometer-calibrated special-edition Kleemann speedometer would need to exceed 240 kph. At mid-day, our section of highway west of Copenhagen was virtually devoid of traffic, making the mad dash to the magic 150-mph barrier a non-event. It was simple: We floored it and held on.

It was almost effortless, with the 5.5-liter supercharged V-8 gulping massive amounts of air, smoothly pushing the near-three-ton beast (with driver and passenger aboard) up through 210, 220, 230, and finally 240 kph. We quit when the 330-kph-limited speedometer read above 245 kph, which converts to 152.2 mph. The ML55K gave us every reason to believe that under the right conditions, with a long enough straightaway, this silver arrow could reach the same 175 mph it did at Nardo.