Changed circumstances can alter your viewpoint. Take the matter of the 2002 Buick Park Avenue Ultra, the biggest of the Buick sedans.

I had uncharitably considered the car a wallow-mobile, a rolling land yacht, an automobile designed more for passengers than drivers.

But that was before a second transplant surgery relegated me to the role of passenger for a month.

During my first week of recovery, a Toyota Highlander wagon/sport-utility vehicle was available. It was a wonderfully crafted machine, a less expensive version of the mechanically and structurally identical Lexus RX300.

The Highlander was loaded with comfort-giving options, too, including heated seats. But, though based on a car platform, it rides higher than most traditional large sedans. That made getting in and out of the vehicle, with two dozen staples in my abdomen, a painful chore. I began to dread having to go anywhere in the Highlander.

The Park Avenue Ultra arrived a week later. It proved to be a blessing, the kindest thing General Motors Corp. ever did for the surgically impaired. Entering and exiting the Park Avenue Ultra was easy, front seat or equally comfortable back. I simply slid in and out. Spring-loaded grips, attached to the roof above the outboard sides of the front and rear seats, assisted ingress and egress.

My chauffeur on these outings, mostly to and from the hospital for post-surgical follow-ups, was my wife, Mary Anne. Lately, she tends to feel hot in even the coldest weather, which is a problem for me. I start shivering whenever the temperature drops below 69 degrees.

But the Park Avenue Ultra offered a solution: individual temperature controls for the driver and the front-seat passenger. In the past, I had considered this feature a technological bauble, a silly thing designed to milk consumers for more money.

But that was when my wife was the front-seat passenger and I was the driver. Little did I know that she would secretly lower the temperature on her side of similarly equipped test cars whenever I raised the temperature on my side to 75 degrees. I used to wonder why she didn't complain. Now I know why.

There were other discovered pleasures in the Park Avenue Ultra. The seats, also equipped with automatic heating, were as comfortable as those found in substantially more expensive cars, including the Mercedes-Benz S-Class and BMW 7-Series sedans.

The ride was soft. But that was perfectly fine with me. When you're hurting, you don't want to feel every bump in the road, and I felt very little in the Park Avenue Ultra.

Handling was not as crisp as found in some European sedans and any number of sports cars. But I didn't give a pahooty about that. What I wanted was maximum comfort, and that is what the Park Avenue Ultra gave. Assuming that convalescence continues going as well as its going, I'll be back behind the wheel soon, and t here will be time and opportunity enough for speed and curves.