Based on sketches by Acura design newcomer Michelle Christensen (when she was just 25 years old), the ZDX employs what Acura is calling Keen Edge styling to alter the usual visual signature of an SUV.With pronounced fender flares, a raked windshield and pronounced tumblehome on the side glass (not to mention that controversial fastback roofline), much of the boxiness of the MDX on which this vehicle is based has been eliminated.As a result, the ZDX projects a carlike image.

Described as a four-door coupe by Acura design staff, the ZDX features hidden rear door handles to exaggerate the two-door look.Since it was intended primarily to meet the needs of self-indulgent couples, the declining roofline is not out of place on a vehicle like this, but it does compromise space in the rear seats.So does the use of long front doors (intended to accentuate the coupe-like proportions), which make the rear doors short and less convenient for access.

Like the exterior design, the interior is unique and employs special materials and bold design ideas to keep the focus on the satisfaction of two privileged passengers.As with Acura's big MDX SUV, the ZDX is powered by a 300-horsepower 3.7-liter V6, now hooked to a new six-speed automatic with manual override control (via steering-wheel buttons).

The sense of privilege inside the leather-lined cabin is unmistakable, and the ZDX reinforces that impression with a plush, well-controlled ride, and the creamy propulsion provided by its sophisticated drivetrain.Throttle response is immediate and authoritative, and the gearshifts are smooth and positive.In keeping with its role, the car's noise levels are low, the climate-control system effective and the entertainment systems bright and clear.

At anything but breakneck pace, the ZDX steers keenly and stays on line with an intuitive accuracy.Only when pressing on hard in the convoluted confines of a canyon road does the big Acura begin to remind its driver that it's a close relative of the company's big MDX.Narrow roads quickly emphasize how wide the car's track is, even if the clever design reduces the visual impression of size, and we were hard-pressed to avoid the Botts dots from drumming through the suspension as we put wheels over the line.

Models with the integrated dynamics system that is part of the Advance Package do better in the twisties, but the ZDX luxury priorities are highlighted by its slightly numb steering and unhurried transmission response.That's all relative to the usual high-fidelity Acura standards, we should add.The ZDX still impresses with moves that belie its considerable size and heft.

The ZDX with Technology Package ($49,995) upgrades to Milano leather interior trim, a navigation system with voice recognition, multi-view rear camera, AcuraLink communication system, real-time traffic updates and weather, an ELS surround-sound stereo system, wireless telephone interface, tri-zone climate control, keyless access with pushbutton starting.

The ZDX with Advance Package ($56,045) includes the Technology Package and adds adaptive cruise control, an active damper system, collision mitigation braking system, blind-spot warning, ventilated front seats, a tricot headliner, a three-spoke steering wheel, and LED-illuminated door handles.

A panoramic glass roof (said to be the longest glass roof in the industry) features an integrated power moonroof.Dual powered sunshades provide shelter from the sun.Wide wheel arches, pronounced shoulders and angular creases provide surface tension to dispel any suggestion of the usual two-box SUV look.Xenon lights are mounted inside asymmetrical housings up front, and there's a stylistic continuation of Acura's chevron grille motif in the lower-bumper apertures.

At the rear, the designers again used distinct panel shapes, tail light outlines and integrated exhaust outlets to embellish the silhouette.A lower glass panel in the rear hatch helps improve rear visibility.

Fitting the leather panel on the sculpted dashboard was quite a challenge, due to the unusual concave shape, and required special techniques.The result, particularly with the saddle-colored combination, is striking, and the textures themselves are rich and pleasing to the touch.

The rest of the interior is very modern in design, with electroluminescent gauges and a center console the Acura designers call the Monolith.Until its backlighting comes on when the ignition is switched on, the console remains blank and dark, with no evidence of the many switches and controls it contains.

Lighting inside the cabin is provided by the large glass roof during daylight hours, and by subtle LED lighting at night.There is over 26 cubic feet of luggage space behind the rear seats, expanding to nearly 56 cubic feet when those seatbacks are folded flat.Access is by the convenient hatch-like rear door, and the liftover height is helpfully low.

Further expansion is possible (for long objects such as golf bags) by removing side panels in the cargo compartment.An underfloor area of about two cubic feet is also available for secure storage.

The front passenger area is both spacious and attractive, but the sloping roofline makes inevitable inroads into rear headroom.Legroom is also not as good in the back, and access is hindered by the small doors and their proximity to the rear wheel well.But adults of average height may still find the rear seats a pleasant place to be for moderate journeys.

Excellent ergonomics make the use of the many devices at hand easy to use.Critical controls are found on the steering wheel, while secondary switches are logically arranged on the dashboard and center console.Voice recognition makes the phone, radio and navigation systems very simple to operate.

Assisted by Acura's SH-AWD intelligent all-wheel-drive system, the new crossover steers accurately and hangs on well in fast turns.The extensive ride-motion control strategy (using magneto-rheological damping fluid that varies its viscosity in response to an electric current to vary shock damping) helps the ZDX retain a plush ride in more sedate applications.In those circumstances, the ZDX's opulent interior and comfortable seating provide an all-encompassing sense of privilege.

While it seems almost eerie to bend a large and heavy vehicle like the ZDX through the tortuous sections of a canyon road and have it stay on line and not wallow, the layer of relentless refinement still makes itself felt with a slightly remote steering feel and gearshifts, even when initiated manually, that are a touch sluggish in response.

In the base model, which goes without the variable damping system, shock tuning is clearly on the comfort side of the equation, yet the ZDX still acquits itself well on tortuous roads for a 4500-pound vehicle.But comfort and isolation are this car's priorities, and drivers needing a more sharply honed experience should probably look at Acura's RDX, which is lighter and more responsive in challenging terrain.

While it's hard to fault the beautiful 3.7-liter V6 engine's smooth and mellifluous performance in most circumstances, it has to be said that most of its power lives in the higher ranges.Torque isn't bad in the mid-range either, thanks to the VTEC variable valve-event technology, but low-rev urge isn't enough to overwhelm the two tons of luxury equipment without help from the obliging six-speed automatic.

Fuel economy is an EPA-estimated 16/23 miles per gallon City/Highway, or 19 mpg Combined.

As for open-road conduct, there isn't much that can waft passengers along with better comfort, quietness and security than these big Acuras.Let's face it, that's what most shoppers in this segment are looking for, and in the ZDX they get it in spades.

Barry Winfield filed this report to NewCarTestDrive.com after driving the ZDX around Beverly Hills and Malibu, California.