Infiniti, like an increasing number of automakers, has gone quaint on us. Harking back to olden days, one has to push a starter button to fire up the engine. That's possible because the M comes with an intelligent key that does not have to be inserted in the ignition. The car senses its presence in your pocket or purse and automatically unlocks the doors for you. Whether we're all going to like this technology enough to embrace it, we're not sure. On the upside, the key can also be programmed to deliver various functions such as pre-opening windows and setting seat and mirror positions.

The standard M35 and M45 have subtle, real rosewood trim with a subdued semi-gloss finish. Sport models have genuine aluminum trim in place of the wood, although the rosewood is available as an option ($600). Chrome trim rings around buttons and gauges subtly enhance the luxury look.

The driver's seat proved comfortable, especially in the Sport model, which features larger side bolsters. It's easy to find an ideal position with the 10-way power adjustments. The ventilated seats warm or cool the derriere with a fan.

There's lots of technology available here and it works well. The optional Bose two-channel audio with Studio Surround sound is exceptionally good. Audiophiles should get it.

The navigation system works well. We like using the birds-eye view, which presents the map in a 3D format that creates a sense of distance and perspective. The voice activation system works well, too, if not quite as well as the system in the Acura RL.

Rear-seat passengers will be happiest with the Premium Package, which adds heated, reclining back seats. The controls are located inside the rear-seat center armrest. The package also includes a DVD system with an LCD that folds out of the ceiling and is controlled with a remote. Separate rear-seat climate control is included with this package.

Even without the Premium Package, the rear seats offer plenty of leg and headroom.

Although the exterior appearance makes the trunk look large, its 15 cubic feet capacity is barely average for this size car, and the opening is on the small side as well. Worse yet, when equipped with the optional full-size spare tire it only holds 11 cubic feet of cargo. At least it has scissor type hinges, which, unlike gooseneck hinges, don't intrude into the usable space. A pass-through opening is provided for carrying skis and other long items.

Overall, we found the living quarters in the M very pleasant. People who bought last year's model agreed. They loved its interior and features, according to a study by J.D. Power and Associates, the market-research firm. In Power's Automotive Performance Execution and Layout (APEAL) study, the 2006 M cars ranked first in the mid-size premium segment, ahead of the Audi A6, BMW 5-Series and Lexus GS.