Acceleration

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
7	7	8	8	7

Any STS is quick off the line, has good midrange passing response. No discernible difference with all-wheel drive. Cadillac reports 7.0 sec 0-60 mph for V6. It claims 4.8 sec for STS-V, and it feels every bit that potent.

Fuel Economy

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
4	4	4	4	4.6

Test rear-drive V6 STSs averaged 14.7 mpg in mostly city driving, 16.2 in mostly highway use. Test AWD V6 averaged 17.7 mpg in city/highway driving. Test V8 averaged 18.8 mpg. Test STS-V averaged 13.7 mpg. V6 uses regular-grade fuel. Cadillac recommends premium-grade fuel for the base V8, requires it for STS-V.

Ride Quality

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
8	8	6	8	6.6

Nice blend of absorbency and firm composure with base suspension and 17-inch tires. Performance Handling Package option triggers mild jitter on coarse or rippled surfaces, even with available Magnetic Ride Control on softest Touring mode. Surprisingly supple STS-V mimics comfortable base-model ride.

Steering/Handling/Braking

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
7	7	8	7	7.2

STS-V good, but no match for sportiest Audi and BMW sedans on twisty roads. Other rear-drive models less athletic, but corner with poise, modest body lean. Optional AWD a boon for snow-belt dwellers. Steering, except on STS-V, overassisted, but informative enough. Optional 18-inch wheels quicken steering response at low speeds, but exaggerate numb on-center feel. Short, straight simulated panic stops.

Quietness

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
8	8	7	8	6.9

All engines accelerate with a muted, refined growl, a bit louder in STS-V. Wind rush impressively low. Cabins very well-isolated overall, though slightly more coarse-surface road noise with 18-inch tires and in STS-V.

Controls

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
7	7	7	7	6.8

STS has relatively few buttons compared to other premium cars--a plus. All controls easy to reach, though some markings puzzle. Available navigation system absorbs many audio functions, but doesn't complicate their use. Quality of interior materials falls just short of import-brand standards.

Room/Comfort/Driver Seating (front)

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
7	7	7	7	7.4

Good head and leg room, but some testers feel hemmed-in by wide center console, high windowsills. Standard power tilt/telescope steering wheel helps dial in comfortable driving stance. Seats' generous side bolsters furnish fine support through turns. View to corners hindered by wide roof pillars.

Room/Comfort (rear)

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
5	5	5	5	5.4

Disappointing for a car in this class. Head room limited for taller riders; intrusion from sunroof housing reduces clearance. With front seats more than halfway back, leg room is cramped and toe space is tight. Seat fairly well-contoured, though longer cushions would enhance comfort.

Cargo Room

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
3	3	3	3	4.2

Trunk space unexceptional for exterior size. Lid hinges don't intrude and liftover is low, but small opening limits size of items that can be loaded. Small rear armrest pass-through from trunk. Average interior storage.

Value within Class

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
6	6	4	5	6.1

STS impresses dynamically, and the availability of all-wheel drive is an asset. AWD is a pricey proposition on V8 models, however, so kudos to Cadillac for making it a stand-alone option on V6s. Inside, STS disappoints with subpar rear-seat space and materials that are not in step with class pacesetters. On any model, extra-cost items can quickly add to the price, making an intelligently optioned V6 version the best value in this line.

Total Score

V6	V6 w/AWD	V8	V8 w/AWD	Class Average
62	62	59	62	62.2

Scores for all Premium Midsize Cars

Low Score		49
Average Score		62
High Score		75