NEW YORK Life is a matter of surprise and compromise. One leads to the other, often in reverse order. If you can get over the business of things not going as expected, you can learn something and move forward.

My associate, Ria Manglapus, and I had grand plans to continue our search for the perfect family car. But we discovered that there is no such thing as the perfect family. We also learned that every family's definition of perfection is different, and that neither income nor class nor familial circumstance can accurately predict what definition a family will choose.

Our learning experience occurred in the most prosaic manner. We were expecting delivery of the 2008 V-6 Chevrolet Malibu LTZ to complete our review of that car line. But several hitches developed in that delivery. A 2008 Mercedes-Benz GL450 sport-utility vehicle arrived instead.

Several problems came with the GL450. It costs at least $25,000 more than the $30,000 ceiling Ria and I arbitrarily had set for the "perfect" family car. The GL450 is not a car. It is a full-size, all-wheel-drive, luxury SUV, albeit one built with car-like unit-body construction.

The GL450 comes with a 4.7-liter, 335-horsepower V-8 engine. It is anything but fuel-economical. The thing drinks only premium unleaded gasoline . . . and lots of it.

Yet, our otherwise sensible families, the people who originally goaded us into looking for the "perfect" family car, were mostly delighted with the GL450 -- a vehicle that neither family would consider in the real marketplace. They were impressed by the luxury of the GL450 -- its panoramic sunroof that framed an azure sky, its supple leather seats, its vast abundance of informational and entertainment electronics, the power and smoothness of its V-8 engine, its seven-passenger seating capacity and, of course, its gleaming Mercedes-Benz tri-star badge.

I drove the GL450 several days before turning over the keys to Ria, an event that brought no small amount of joy to the Manglapus family, which was planning a trip to Bryce Mountain, Va.

I was surprised by the GL450's lightness of being. It has a curb weight -- weight with factory-installed equipment and fluids -- of 5,280 pounds. Yet, largely due to its tight, aluminum-intensive, unit-body construction, it drove and handled like a much lighter vehicle. It is no exaggeration to say that its entire road performance was surprisingly, pleasingly sports-like.

Yet, there was no way that I was going to drive the GL450 to New York to assist my daughters in a medical emergency that, as life happens, turned into one of my own. New York has a thing about SUVs. It hates them. Many New York garages will charge you $10 to $20 more a night to park them.

So, I chose to return the tested-and-reviewed (On Wheels, Feb. 24) 2008 Chevrolet Malibu Hybrid sedan to General Motors' New York office instead.

As I said, my decision brought great rejoicing to the Manglapus clan . . . for a while.

"I was happy that we were getting something with seven seats. But it turned out that we could not possibly carry seven people and all of their luggage in the GL450," Ria said, conceding that luxury does not necessarily mean maximum utility.

Still, there was joy in Mangalpusville -- the leather, the sunroof, the power, the mobile entertainment venue that included video, and the Mercedes-Benz badge.

Then came fill-up time. Horrors! Close to $85 for a full tank. Ria returned the GL450 with a request: "Please tell me that somewhere there is a seven-passenger or eight-passenger vehicle that can carry more luggage and not cost a fortune to operate."

There is, Ria. In fact there are several of them, all of which we will review in this space.