The last time I was in a Mercedes-Benz diesel I was 9 years old. My mom drove one. From inside my school classroom, I could hear her driving up the road; I could smell it from across the street. It was embarrassing to my 9-year-old self. Imagine my joy at discovering that the 2009 Mercedes-Benz R320 BlueTec diesel is not only quiet and odor-free, but kind to our planet, too.

The R-Class crossover is already close to becoming the ultimate luxury mom-mobile, and it's glamorously green with its new diesel technology, too. Apparently, this is what all the eco-groovy Hollywood moms are driving. After spending a week in an R320 diesel, I'd be happy to join their ranks. If only...

The R-Class is a six- or seven-seat crossover with so much luxury and comfort inside that calling it a station wagon is just plain insulting. It's a pretty, powerful and flexible crossover. While I wasn't in love with Mercedes' complicated Comand information system or the layout of the controls, I wasn't annoyed enough to be happy to see this car go.

Driving the R320 diesel is surprisingly pleasant. There's none of that nasty noise or smoke that used to come with diesel engines. While this new diesel is a bit louder than its gasoline counterpart, the sound level isn't annoying or that noticeable. In fact, I had to draw people's attention to the R320 to get any sort of reaction to it. The diesel V-6's sound is deeper and slower, but it's easily within the normal range of engine noise. Another great improvement over my mother's diesel car is the BlueTec engine has eliminated the dreaded diesel lag. The crossover's acceleration seems heavy rather than quick, but it's certainly powerful. It drives smoothly and steadily, and it handles curves and mountain roads without batting an eye.

What's really great about the R320 is its gas mileage and the eco-friendliness of the new diesel technology. The R320 gets an EPA-estimated 18/24 mpg city/highway. Even with my lead-footed driving through the mountains, I averaged 17 mpg, which is decent for a car this heavy. It's not just the gas mileage that's green, the additives to the exhaust system negate 99 percent of those icky greenhouse gases and particulates that used to come pouring out of diesels as black smoke.

Exterior

I'm just going to say it: In black, the R-Class looks like a hearse. It's not just me; I've heard this from lots of people. However, the R-Class is beautiful in a lovely Alpine Rain Metallic paint. A friend of mine called it "dreamy." This isn't your mama's station wagon. It's sleek, elegant, classy and all kinds of things that I'm not.

There's great visibility thanks to the large windshield. The chrome grille is stamped with the famous three-spoked symbol, and the oval headlights recall the Mercedes-Benz of a bygone era. The R-Class' tinted windows are trimmed with a thin band of chrome. A sleek ridge along the doors creates movement, and the standard 19-inch wheels bring authority to the R-Class. There's enough chrome to add some sparkle and richness to the R320, but not enough to be gaudy or flashy. Everything is tasteful and elegant. Just stay away from the black one. It's ominous.

From the side, however, the R-Class looks like (forgive me for saying it) an elongated station wagon, but I wouldn't call it unattractive. That elongation is what creates room for a fully functional third row that's incredibly easy to get to because of the R320 diesel's enormous rear doors. Honestly, these are the largest rear doors I've ever seen not attached to a limo. They're huge! They open so wide that my kids struggled with them a bit, but loading an infant-safety seat is significantly easier when the door isn't bumping you in the butt. Unfortunately, when little people fling those massive doors open, nearby cars are bound to suffer dings and indignities aplenty.

I was impressed with all the room in the R320 BlueTec. Even with the third row in place, there's plenty of space in the cargo area for a major grocery run. My test car didn't come with the optional power liftgate, so I had to open it the old-fashioned way; the liftgate didn't feel heavy and was easy to manage, if less fun than pressing a button.

Because the R-Class is a crossover - not an SUV - it doesn't sit much higher than a sedan. There's no climbing involved, unless you're getting to the third row, and even that's easy.

SENSE AND STYLE

Family Friendly (Not Really, Fair, Great, Excellent): Excellent

Fun-Factor (None, Some, Good Times, Groove-On): Good Times

Interior

The R320 diesel's interior is bright and luxurious. Large windows and a fabulous panoramic sunroof bring in the rays and offer great visibility. That panoramic sunroof is a $1,050 option, but it's oh so worth it. It makes a rather long and solid car feel light and airy. A power sunshade can block out the sunlight at the touch of a button, but I loved having all that sunshine in the car and only closed it at high noon. It amazes me that the R320 is so quiet inside, even with all that glass. If I turned off the audio system, I could hear the engine. With music playing at modest volume, I heard nothing from the outside.

With several covered bins to contain all my gear and a terrific USB input for my iPod, I was a happy camper. I connected my phone to the Bluetooth system with no trouble at all, and the sound was crystal clear.

The test model I drove lacked some of the pricier bells and whistles, like satellite radio and a navigation system. While I didn't miss the Siruis Satellite Radio or the nav system, I did wish for a backup camera. A backup camera is available in two different option packages, costing $5,350 or $7,850. Visibility is pretty good from most angles, but there just isn't any way to see what's directly behind you without a backup camera.

The R320 diesel's many buttons on the center stack are within reach, but most of the car's systems are controlled with the Comand system. It uses a large, multidirectional knob that's surrounded by four "soft" buttons. The system takes some getting used to. Honestly, between the Comand system and all the buttons on the dash, I struggled with simple things like changing the radio station or turning down the air conditioning. So, I did what I rarely do; I opened the owner's manual. Whoa, was that a mistake. The owner's manual has esoteric pictograms that seem to have little or no relationship to their purpose, which is worse than the crossover's rows upon rows of buttons.

There were a few things that bugged me about this car. The turn-signal stalk sits lower on the steering-wheel column than in most cars, and the stalk for the cruise control sits just above the area I'd expect the turn-signal lever to be. I often found myself engaging the cruise control rather than signaling an upcoming turn. It was particularly annoying because the turn-signal stalk is out of sight, hiding behind one of the steering-wheel spokes. The leather-wrapped steering wheel feels great, and it has controls for the audio system, your cell phone and voice-control options. However, I ran into trouble with those buttons, too. If I didn't press them firmly enough, nothing happened. If I pressed them too firmly, the horn honked and I looked like an idiot. I don't like looking like an idiot.

Most of the time, however, I enjoyed all of the R320 diesel's comfort and luxury. The second-row seats are captain's chairs that fit passengers of all sizes. It took awhile to get our high-back booster seat situated in the seat because the active head restraint kept getting in the way. We worked out a solution, but it took awhile. The seat belts were easy to use and fit my guys well. There are four sets of Latch connectors in the second and third rows, but they're really buried and hard to get to.

What wasn't easy for them was the cupholders in the backseat. Rather than seat- or door-mounted cupholders, the R320 diesel sticks them near the floor on the back of the center console. You have to open a door and then fold the cupholders down; this isn't feasible for someone strapped into a child-safety seat, and it's too complicated for little fingers.

In the third row, the cupholders are set just below the windows and within reach. In fact, everything about the third row is easy, from the easy entry - the second row magically slides/folds/scooches out of the way - to the easy-to-use remote folding of the seats. Seriously impressive.

IT'S THE LITTLE THINGS THAT COUNT

Storage Compartments (Puny, Fair, Ample, Galore): Ample

Cargo/Trunk Space (Puny, Fair, Ample, Galore): Ample

Safety

The R-Class has been named a 2009 Top Safety Pick by the Insurance Institute for Highway Safety. To earn this honor, a car must receive the highest rating of Good in front, side and rear crash-tests and have stability control.

The R320 diesel also has Mercedes' Pre-Safe automated collision-mitigation system, which quickly and automatically prepares the crossover for a crash by tightening seat belts, among other things. There are front-impact airbags for the driver and front passenger airbags and side-impact airbags in all three rows. Side curtain airbags also cover all three rows of seats.

On top of stability control, the R-Class has standard all-wheel drive, traction control - which is great on slippery surfaces - antilock brakes and a tire pressure monitoring system. This alerts you should a tire suddenly lose pressure. Even if you have a blow-out, you won't get stuck changing a tire on the side of the road because the R320 diesel comes with run-flat tires.

The R-Class has a long list of optional safety features, including a backup camera and a blind spot monitoring system. There are rollover sensors and Trailer Stability Assist, in case you ever tow something behind the R-Class. The R320 diesel's SmartKey never has to leave your pocket or purse, so there's no fumbling in the dark for keys. However, there's a panic button on the key fob should you feel the need.

FAMILY LIFESTAGE

In Diapers: Wide-opening doors make loading child-safety seats easy, as do the four sets of Latch connectors.

In School: The big, heavy doors guarantee lots of door dings, courtesy of little arms.

Teens: The entertainment choices, as well as uber-comfy captain's chairs, will please teens.