Road Test The biggest flaw in the otherwise ideal powertrain begins to rear its ugly head the moment you step on the gas. And a slight surge keeps the brake pedal from responding progressively, which in turn makes smooth stops hard to come by.

When it comes time to get the 2006 Mercedes-Benz CLS500 rolling, the big V8 accelerates strongly enough that the manufacturer’s impressive six-second 0-to-60 time is easy to believe. Part of the credit goes to the Sportronic transmission’s knack for selecting just the right gear even when left in the fully automatic mode.

The biggest flaw in this otherwise ideal powertrain’s performance begins to rear its ugly head the moment you step on the gas. There’s a slight hesitation that causes you to feed in more throttle, which then results in a surge of acceleration. While this sort of hiccup is common to many models that have replaced a physical linkage between the accelerator pedal and the engine with an electronic “drive-by-wire” connection, it’s the kind of small annoyance we can imagine might grow into a major irritation over time.

Once underway the CLS500’s standard electronically controlled air suspension continually adjusts ride height as well as damping and spring rates to suit existing driving and road conditions. The suspension also includes a console-mounted button that allows the driver to cycle through three progressively firmer settings – Comfort, Sport 1, and Sport 2 – to dial up just the right ride/handling balance for everything from comfortable interstate cruising to carving turns on a twisty section of mountain road. The suspension system also includes a self-leveling feature that automatically compensates for heavy loads. A separate button allows the driver to raise the body by one inch for travel over rough roads.

The same speed-sensitive rack-and-pinion power steering used in the E500 delivers precise and progressive control. That said, we think a lot of driving enthusiasts will find themselves wishing for a little more weight in the steering effort.

When it’s time to hit the brakes, large four-wheel discs – 13-inchers up front and 11.8-inch units out back – bring the CLS to a rapid halt. Advanced braking technology, including four-wheel ABS with electronic brake-force distribution and electronic brake assist, helps keep things under control during hard stops.

Here too, however, the electronic gremlins common to drive-by-wire systems make their presence felt. A slight surge keeps the brake pedal from responding progressively, which in turn makes smooth stops hard to come by. Again, this may seem like a small nit to pick but the car’s overall level of sophistication – not to mention its steep price tag – make these problems stand out in stark relief.