The Good: The 2006 Buick Lucerne CXS has respectable tech offerings, including a stereo with auxiliary input, MP3 CD compatibility, and XM Satellite Radio, as well as optional touch-screen navigation. The meaty Northstar V-8 delivers plenty of top-end power to enjoy from the leather-trimmed interior. The Bad: The 2006 Buick Lucerne CXS's four-speed gearbox is sluggish around town and delivers underwhelming gas mileage. Mediocre fixtures, basic instrumentation, and a price tag of nearly 40 grand mean you don't get a whole lot of bang for your Buick buck. The Bottom Line: With plenty of standard onboard tech, a comfortable interior, and a premium V-8 under the hood, the 2006 Buick Lucerne CXS lives at the top end of the midrange sedan market. Unfortunately, its price tag suggests something more impressive. The 2006 Buick Lucerne CXS is not at all bad for a Buick. The top-of-the-range model (it also comes in CX and CXL versions) is spacious, with leather seats and a range of climate-control options, making for a comfortable ride. Technology features on our test model were numerous and usable. Harman Kardon's audio system with MP3 CD compatibility, auxiliary input, and satellite radio was the most impressive cabin feature, but others such as climate control, heated seats, reverse-parking assistance, and optional touch-screen navigation added to the car's luxury feel.The 2006 Buick Lucerne CXS looks good from the outside, with sleek lines, chrome detailing, and handsome 17-inch alloy wheels. Nor is its beauty skin deep: GM's V-8 Northstar gives the CXS boasting rights on the parking lot and the performance to back them up in the fast lane. On the downside, Buick could have done better with cabin fixtures, and the four-gear automatic limits in-town performance.The base price for the 2006 Buick Lucerne CXS is $34,265. Our test car came with the Driver Confidence Package ($595), heated and cooled front seats ($500), a six-disc MP3 CD player ($100), and Premium Paint ($995). With a destination charge of $725, the total ticket price was $37,480.Buick touts the 2006 Buick Lucerne CXS as the ultimate combination of elegance and innovation--but it isn't. However, having dispensed with the hyperbole, there is a range of comfort and tech features that makes this car stand out from the crowd--and head and shoulders above Buick's regular stripped-down offerings. Perforated leather seats with temperature control and electric lumbar support welcome the CXS driver to the cabin, and interior chrome accents and a leather-bound steering wheel go some way to mitigating the tacky faux walnut on the dash and the center console.Two options for seat heating and three levels of seat cooling offer more than adequate allowance for different seasons. The coldest setting felt as if we were sitting on ice cream--effective, if a little disconcerting. Dual-zone climate control allows the driver and the front passenger to have some autonomy over their respective temperatures but is obviously limited by shared airspace; the in-seat controls are the only way of ensuring a truly personalized temperature.Heated and cooled front seats give the driver and the passenger a range of options for staying comfortable in different climates.A turn of the ignition key launches the 2006 Buick Lucerne CXS's driver information center (DIC), the car's main instrumentation interface. Our test model didn't come with the optional DVD-based touch-screen navigation system, which we would have liked to try. The DIC's dot-matrix LCD occupies the bottom half of the speedometer and is controlled by four buttons to the right of the steering wheel. Using these buttons, you can set the display as an odometer or a tripometer or to provide information on the Lucerne's average and instant fuel economy, as well as data from GM's oil life and tire-pressure monitoring systems.The DIC can also be used to activate and deactivate the ultrasonic rear-parking-assist system, which uses a color-coded light meter situated on the lip of the parcel shelf, along with a series of beeps to alert the driver to obstacles when reversing. We found the meter to be well placed and useful for gauging decreasing proximity to obstacles. One complaint that we have is that the lights are difficult to make out in bright sunlight--a criticism we also had of the main gauges in the instrument panel, which are a washed-out gray rather than white.The Lucerne's ultrasonic rear-parking-assist system uses three lights to inform the driver of proximity to objects while reversing. Harman Kardon's nine-speaker, 280-watt audio system comes standard on the 2006 Buick Lucerne CXS and delivers solid but not outstanding sound quality at all ranges up to half volume, after which it starts to get noisy. In an unofficial barometer of onboard acoustics, we found that when cranking up the sound, the image in the rearview mirror distorted, due to vibrations before the bass distorted. The system offered an array of audio-source options, including XM Satellite Radio, MP3 compatibility (both discs and portable players via an auxiliary input), a six-disc CD changer, and AM\/ FM radio.Navigation of MP3 files is intuitive via buttons and a dial on the stack, and ID3 tags are accessible at the touch of a button. For XM Satellite Radio tracks, the stereo's LCD provides impressive data points such as channel, song, artist, and category.The standard Harman Kardon audio system provides easy navigation of MP3 folders and files, as well as track and artist information for XM Satellite Radio broadcasts.Despite the ease of use via the 2006 Buick Lucerne CXS's head unit, we had more difficulty getting around the audio system using the controls mounted on the steering wheel, which allowed us only to skip forward, and required a deal of wrist action to adjust the volume via paddles mounted behind the steering wheel. Another button on the steering wheel acts as a voice controller when communicating via GM's OnStar telematics service (one year's Directions and Connections package comes standard on all Lucerne models), as well as a mute button for the stereo the rest of the time. Although an in-dash navigation system is an option, Buick relies on the OnStar service for navigation and phone connectivity. The disadvantage of OnStar over Bluetooth cell phone integration is that the car needs its own telephone number.A couple of other small tech features endeared the car to us, including a digital compass built into the rearview mirror, as well as illuminating orange blinker arrows on the wing mirrors, which are far more useful in the dark than in the day. The windshield wipers also use GM's RainSense system to activate when a wet windshield is detected. We didn't test this system due to the fine weather we had while driving the car.If there is a star feature in the 2006 Buick Lucerne CXS, it is the engine. While onboard tech and comfort are adequate, it's this car's 4.6-liter, 32-valve V-8 Northstar power plant that differentiates it from its 3.6-liter V-6 CX and CXL siblings (although the V-8 is offered as an option on the latter) and from other upper-middle-class sedans. It also goes some way to justifying its near-$40,000 price tag.The 2006 Buick Lucerne CXS marks the first time GM has installed its flagship engine in anything less than a Cadillac, and with around 275 horsepower, the car has plenty of muscle. In a sign that GM is proud of this model, the parent company has placed a branded chrome GM badge on the front wing to let people know that this car comes from the General Motors stable.GM makes its mark on the 2006 Lucerne CXS in the shape of a branded badge on the car's front fenders.Unsurprisingly, the Northstar is happiest on the freeway. After tailing a Jaguar X-Type on the way to San Jose, we prevailed upon the driver to cede the fast lane, and with 295 pound-feet of torque at 4,400rpm at our disposal, we saw him only once more--in the rearview mirror.Around town, the 2006 Buick Lucerne CXS's V-8 is a tad lethargic, taking a while to make up its mind off the line and producing noticeable torque steer for those in a hurry. Also, with only a four-speed automatic transmission, flexibility at lower speeds is limited. Suspension and handling are both sound, enhanced respectively by Buick's magnetic ride control and StabiliTrak. However, a slight understeer had us stretching a couple of extra millimeters to change lanes in town.The Buick Lucerne is the first car other than a Cadillac to get GM's V-8 Northstar engine.From the cabin, the 2006 Buick Lucerne CXS is a quiet car: We recorded a reading of 65dB in highway driving at 60mph. Fuel economy, however, is less impressive. EPA gas mileage ratings for the V-8 are 17mpg in the city and 25mpg on the highway, but we recorded an average of just 17.9mpg in a mixture of in-town and freeway driving. EPA air-pollution ratings for the V-8 are between 6 and 7 out of 10 (with 10 being the cleanest), as well as 6 out of 10 for the 3.6-liter V-6--not bad for a thirsty V-8.An array of standard safety features and a solid design make the 2006 Buick Lucerne CXS a safe bet. Each Lucerne model comes with six air bags as standard, including roof-rail curtain air bags and a dual-depth front-passenger air bag that has two deployment settings, calibrated to the severity of an impact.StabiliTrak's brake-assist feature senses emergency-braking situations and increases braking at each wheel as necessary. The Lucerne has a maximum five-star rating for driver and passenger frontal impact, five stars for rollover safety, and four stars for front- and rear-seat side impact.The 2006 Buick Lucerne CXS comes with Buick's comprehensive four-year\/50,000-mile bumper-to-bumper warranty, which includes corrosion coverage, roadside assistance, and courtesy transportation. Rust-through coverage is offered for six years with unlimited mileage.