The Good: Bluetooth integration; steering-wheel and voice controls; keyless entry and ignition; crisp Multi-Media Interface display. The Bad: No traffic information with navigation system; Multi-Media Interface requires dedication to fully exploit; harsh city ride with Sport suspension; prominent snout. The Bottom Line: The 2005 Audi A6 4.2 Quattro has the performance, the interior appointments, and the presence to hold its own against very capable and entrenched rivals. 2005 Audi A6 QuattroAudi improved its midsize sedan across the board, with the possible exception of the new familial grille treatment. Adding a substantial 3.2 inches between the wheels but less than half that in overall length, the new 2005 Audi A6 4.2 Quattro now stretches out 193.5 inches and offers impressive handling and performance when equipped with the V-8 and Sport suspension options. A full list of standard in-car gadgets complements top-notch materials and design to make the A6's cabin among the best in the business. Options such as the navigation system and satellite radio are integrated nicely into the Multi-Media Interface (MMI) and allow the use of voice commands, enhancing the overall driving experience rather than overwhelming the driver with potential distractions. We found the MMI particularly usable, even though it lacks a touch screen, but some of the A6's amenities require time spent studying the owner's manual. Accessible systems Audi continues to produce interiors that rank among the best available in the sport-luxury realm. High-quality materials such as real wood, brushed aluminum, and Volterra leather give an air of relaxed elegance, while well-designed electronic controls mean the car's impressive performance can be tapped with minimal distractions from the dashboard. Steering-wheel controls consist of two scrollwheels and a mode button that let you select satellite and broadcast radio stations and CD tracks from scrolling lists. Redundant displays in the center of the gauge cluster and on the MMI screen help keep the focus on the road. The climate controls are mercifully separated from the MMI system, allowing simple adjustment for both driver and passenger. The more in-depth features of the MMI, such as voice activation, will demand a degree of dedication to master, but an owner willing to put in the time will be rewarded with lots of electronic control. Systems from interior lighting to crosshairs on a map to a readout of battery power are available via the center console-mounted twist-and-click knob and four surrounding buttons of the MMI.The center click-knob and the four corner buttons of Audi's MMI, along with the hardwired buttons along the sides, let you easily get to the car's functions.The optional DVD navigation system is reasonably intuitive for basic operations, but configuring the route map to display your preferred combination of services and landmarks, for example, can be time-consuming and frustrating to the uninitiated or anyone averse to reading the owner's manual. A cell phone cradle under the center armrest allows the integration of non-Bluetooth-capable phones with the system, but in a car whose key can stay in your pocket while driving, a phone that can stay there too seems the right choice. We found the A6 Bluetooth network pairs up painlessly with a phone, and it includes advanced features such as storing contacts.Our car's sport seats were very comfortable, the driving position helped by full-power adjustments, including movable lumbar support, and a power-tilting and power-telescoping wheel. Road noise is nicely isolated, although probably not helped by our car's larger wheels and thinner rubber; we measured 71db at a steady 60mph. From the outside, the A6 has sharpened its edges since its debut for a more muscular overall appearance. The use of chrome accents at the front of the car and around the side windows is restrained and tasteful.Calculated road holding The 4.2-liter, aluminum-alloy 40-valve V-8 engine with variable intake-valve timing hustles the A6 along with alacrity. Fed through a six-speed automatic with Tiptronic manual control, the engine's 335 horsepower represents plenty of useful power. A sport mode moves upshift points slightly higher in the rev range, giving better acceleration when the need or desire arises.Audi's now-familiar Quattro all-wheel-drive system, working with the Electronic Stabilization Program (ESP), keeps the A6 planted and putting down power at the wheels with the most grip. ESP incorporates standard ABS, an Electronic Differential Lock, and Anti-Slip Regulation to bring the car's path in line with the intended path, calculated using lateral acceleration, braking force, and steering-angle data in addition to the ABS wheel-speed sensors.The Servotronic variable-assisted steering feels particularly precise together with the Sport suspension package's 18-inch alloy wheels, with steering effort seeming almost constant from parking lot to onramp but with proper feedback felt at speed. Some of our testers thought throttle tip-in was oversensitive, but this point remained in contention.The Audi-standard red LED lights in the center display show radio and navigation information, also found on the MMI screen, to help keep the driver focused on the road.Pockmarked city streets and construction season's raised steel plates are not the kindest canvas for the Sport suspension's stiffer ride, it must be noted. But on a smoothly curving road, all is forgiven, and the Audi has closed the gap on the revered BMW 5 Series in terms of seat-of-the-pants road-holding. With the wheels spread out slightly from the previous A6, the car feels solid on the road and especially confidence-inspiring at highway speeds. We observed acceleration from 0 to 60mph in the seven-second range with the V-8, varying slightly depending on the transmission mode.Headlights that turn The reassuring list of safety features in the A6 runs from the simple but smart to the advanced. Front, side, and side-curtain air bags are present, as expected in this class of car, with a weight-sensing front seat that turns the passenger's air bags off should a child seat be belted there. A nod to performance with a welcome safety benefit is a tire-pressure warning system incorporated into the MMI and allowing for recalibration following wheel changes or significant load variations. The bixenon headlights feature an adaptive function that directs their beams to better illuminate curves based on steering-wheel angle.An energy management system distributes electricity to various components as needed to keep the battery charging efficiently and ensures starting power remains available for as long as possible if the car stands unused. Audi's factory warranty covers 4 years or 50,000 miles and includes all scheduled maintenance during the warranty period. Corrosion protection runs to 12 years. Third-party roadside assistance is included for 4 years.