Mercedes-Benz E250 CDI: One flaw short of fantastic

FROM SINDELFINGEN, GERMANY — Several years ago, while on assignment for a magazine, I participated in an experiment with Mercedes-Benz that involved my being wired up like a lab monkey and driving across the Austrian Alps in an E500, some 10 hours of hellbent berggeblitzen (not officially a German word). These biometric readings were later plotted against the car's telemetry in an effort to measure the effects of fatigue on my driving. Given my superhuman talents and composure behind the wheel, naturally, the effects were negligible.

Especially because I unplugged the monitors and took a two-hour nap at a rest stop.

Wrote the story, cashed the check, and that was that. Until Thursday, when I got into the new-for-2010 E-class and discovered the Attention Assist system, which -- lo and behold -- detects the gradual raggedness in driver inputs that betray drowsiness. The boys in white lab coats have been busy.

If the car senses erratic steering and rapid corrections, the telltales of fatigue, the Attention Assist will advise you to get some rest as it displays a big coffee cup icon in the instrument panel (this is my favorite ISO 9000 icon, by the way). Attention Assist is just one of a dozen or more marquee safety systems Mercedes has piled onto the E-class for 2010, and it's clear at the outset that Mercedes is returning to safety as a transcendent brand value after years of marketing itself as the spoils of well-paying bad behavior, the glittery metal floss under Britney Spears' untrussed derriere.

Suddenly, the E-class is, again, the car for grown-ups.

I won't parrot the company line about the E-class being the heart and soul of the brand, except that it is. The E-class is a "business saloon," the standard-issue Mercedes -- stout, reliable, comfortable and enduring. This is the stainless-steel Rolex of cars, steadily elegant and appropriate for any occasion, and you have to admire the alacrity with which the E-class can go from being a tan airport taxi drone in Berlin to being a valet-park star in Beverly Hills.

To save you the suspense, I'll tell you now: The new E-class is a fantastic car but for one huge, agonizing, inexcusable error that baffles me like a Rubik's Cube the size of the Seagrams Building. More on that in a moment. For now, consider a short list of some of the more fun safety systems available on the E-class as standard or options.