Most cars reveal themselves under everyday conditions. The A8, Audi's most opulent sedan, makes its strongest impression when the road turns rough. Literally. I was cruising down a city boulevard enjoying a surprising respite from traffic, thinking I had it made, when the pavement suddenly turned into a sea of rutted canyons, probably dug up by road crews days earlier and forgotten. I braced for a jarring impact with the rubble, and as I rolled onto it I felt . . . practically nothing. Somewhere between the tires and my clenched hands, the A8 reduced the shock waves to a minor quiver.

That's the kind of pampering you get for $70,000. Down at street level, where that kind of cash might be more appropriately put toward a house than a car, it's hard to evaluate whether an extra 40 or 50 thousand is worth paying to remove many of the routine stresses from the driving experience. But if you forget about the money for a moment (we can all pretend, right?), it sure is lovely to ride with the technological equivalent of a butler. At night, the A8's recessed floor and door lighting creates the ambience of a private Gulfstream, whisking you off to St. Bart's. The seats mold to your body like neoprene. If those touches don't soothe you–and even if they do–you can always relax a bit more by pushing the optional "massage" button on the front seats, sending a roller plowing up and down your back as you drive.

The A8 takes a familiar place next to the other German sedans in this rarefied class. It is not quite as feisty as the BMW 7 series, lacking the 7's surreal handling on curves. And it isn't as stately as the Mercedes S-Class, the standard setter for regal luxury. But like other Audis, such as the A4 and the sprightly little TT coupe, the A8 combines artistic styling with precise, thoughtful engineering. Many of the storage bins and other gizmos, along with the centralized digital display screen, recede into the molding at a touch, creating a seamless elegance in the cabin. The center armrests are curved and tapered, like modernist furniture, and they can be ratcheted up to whatever position suits the occupants. As for performance, the A8 is like a power lifter wearing an Armani suit: There are some whopping muscles rippling beneath the refined exterior.

The A8 scores another important point with its "multimedia interface," or MMI, the fancy term for the system that controls the radio, climate, navigation system, and other functions. Managing all of that clutter has become an underappreciated art for car designers, with some notorious DOS-like creations, most notably the iDrive on the 7 series. The MMI is much more intuitive and easier to navigate. Through a combination of dashboard buttons and on-screen menus, you can find most of what you want in a couple of easy steps. And in many cases, the MMI isn't just more sophisticated; it's actually simpler and more functional. There are no radio presets, for instance. Instead, the MMI picks out the stations you tune into the most and puts them atop a list of all stations available; then you scroll down to the one you want. I sure wish you didn't have to pay $70,000 for such cool features. But since you do, I'm reconsidering how to spend my house fund.