Acceleration

A8 L	A8 L w/19-inch wheels	S8	Class Average
7	7	9	7.3

No W12 or regular-length A8 models have been made available for us to test. A8 L feels strong at any speed. Some of our testers complain of overly sensitive low-speed throttle action. The transmission's performance-oriented Sport mode helps offset somewhat lazy low-speed downshifts. S8 models deliver outstanding thrust at any speed, with crisp yet smooth shifts. Audi claims 4.9-sec 0-60 mph, which feels accurate to us.

Fuel Economy

A8 L	A8 L w/19-inch wheels	S8	Class Average
3	3	1	3.3

In Consumer Guide testing, A8 Ls averaged 15.9-17.1 mpg in city/highway driving, 18.2-19.0 in mostly highway use. No opportunity to measure with the S8. Audi recommends premium-grade gas.

Ride Quality

A8 L	A8 L w/19-inch wheels	S8	Class Average
8	7	6	8.2

Generally absorbent, though the A8's available 19-inch tires generate unseemly impact harshness over sharp ridges. Stable at speed, but large bumps can induce unsettling wallow with the adjustable suspension left on one of the softer settings. S8's 20-inch tires and sport suspension make for an even firmer ride regardless of suspension setting, but it's not overly harsh.

Steering/Handling/Braking

A8 L	A8 L w/19-inch wheels	S8	Class Average
8	8	8	6.9

A8's steering is firm and accurate, though a little light at lower speeds. AWD provides reassuring grip, but the available 19-inch tires do little to enhance control and balance vs. the 18s. Fast corners induce moderate body lean unless the driver selects the firmest suspension settings. Excellent braking control. S8 is slightly more agile all-around.

Quietness

A8 L	A8 L w/19-inch wheels	S8	Class Average
9	8	7	8.4

Most always whisper-quiet, though the 19-inch tires rumble and whine a bit on coarse pavement. S8's 20-inch performance tires introduce more road roar. The V8 engine sounds rich, while the S8's V10 emits an exotic-sounding growl under throttle.

Controls

A8 L	A8 L w/19-inch wheels	S8	Class Average
5	5	5	5.8

A8's large gauges are clearly marked. Conventional switches handle only basic audio and all climate functions. Other adjustments require the use of Audi's MMI (Multi Media Interface) with center-console knob, four flanking buttons, and dashboard screen. This system is not intuitive, and it complicates what should be simple controls for the audio and navigation system. The navigation-system screen retracts into the dashboard when not in use.

Details

A8 L	A8 L w/19-inch wheels	S8	Class Average
9	9	9	8.4

The cabin in the A8 boasts top-notch materials and sophisticated design that stand out even in the high-buck segment. S8's interior leans more towards sporty rather than opulent, but it's still classy.

Room/Comfort/Driver Seating (front)

A8 L	A8 L w/19-inch wheels	S8	Class Average
10	10	10	8.8

Ample room on firm, wide seats with excellent support. Split center console customizes armrest heights for driver and passenger. Outward visibility is impeded by the rear headrests and side roof pillars. S8's sport seats offer excellent lateral support but aren't confining.

Room/Comfort (rear)

A8 L	A8 L w/19-inch wheels	S8	Class Average
10	10	9	7.9

Regular-length models furnish bountiful legroom even with the front seats fully aft. Longer A8 L and W12 offer limousine-like legroom. The contoured ceiling provides good six-footer headroom. Large, wide door openings make for easy entry and exit.

Cargo Room

A8 L	A8 L w/19-inch wheels	S8	Class Average
4	4	4	4.1

A8's spacious flat-floor trunk has a high-rise power lid, large opening, and low liftover. Interior storage is enhanced by pull-open portfolio-sized pockets on all doors.

Value within Class

A8 L	A8 L w/19-inch wheels	S8	Class Average
8	7	6	5.5

Audi's flagship A8 trumps rivals for interior decor, standard all-wheel drive, and, depending on model, base price. A8s can overwhelm with high technology, and the air suspension doesn't provide an ideal ride/handling balance. Still, these are formidable premium large sedans by any measure and Recommended picks in this class.

Total Score

A8 L	A8 L w/19-inch wheels	S8	Class Average
81	78	74	74.6

Scores for all Premium Large Cars

Low Score		67
Average Score		74
High Score		87