STS comes standard with leather trim, dual-zone automatic climate control, Bose AM/FM/CD stereo, the usual lineup of power creature comforts and driver aids, OnStar telematics (with one year's service), Stabilitrak electronic stability control, automatic headlamp high-beam control, and rear park assist.

The popular V6 Luxury Package ($2640) includes a Memory Package with dual eight-way power and heated front seats, power tilt and telescoping steering wheel with radio and climate control settings; four-way power front lumbar seat adjusters; an eight-speaker stereo with six-disc CD changer; rain-sensing wipers; polished aluminum wheels and memory for driver's seat, outside mirrors and steering wheel settings; offered as an add-on to this package are satellite radio, programmable garage door opener and eucalyptus wood interior trim ($730).

The V6 Luxury Performance Package ($8,285) adds 15-speaker surround-sound Bose stereo with in-dash six-disc CD changer, DVD-based navigation, Bluetooth phone interface, heated rear seats and ventilated/heated front seats, Eucalyptus wood trim, leather-wrapped wood-accented heated steering wheel, tilt/slide power sunroof, auto-dimming inside rearview mirror with OnStar controls, outside automatic recirculating air quality sensor, tire pressure monitoring system, universal home remote, decklid spoiler, and performance brakes; a heavy-duty cooling package ($150) can be added to this. Stand-alone options include a performance handling package ($795), Bose surround-sound stereo ($2,590), premium leather seats ($1,200), 18-inch polished aluminum wheels ($800), power moonroof ($1,200) and an engine-block heater ($100). Two of the nine exterior paints, Infrared and Diamond White, cost extra ($995).

The V8 Luxury Package ($4,445) includes the Memory Package, auto-dimming inside rearview mirror, heated front and rear seats, four-way power lumbar adjusters, Bose surround-sound stereo and navigation system, heated leather-wrapped steering wheel, universal home remote, and Eucalyptus wood trim. The V8 Luxury Performance Package ($10,740) adds an outside automatic recirculating air quality sensor, ventilated front seats, leather-wrapped wood-accented steering wheel, power sunroof, tire pressure monitoring system, more extensive Eucalyptus wood trim, Intellibeam Xenon headlamps and washers, a decklid spoiler, and performance brakes. The Premium Lux Performance Package ($12,790) adds premium Tuscany all-leather seating to the Luxury Performance Package list.

Adaptive cruise control ($2,300) is available for both models. A Performance Handling Package ($795) with special springs and shocks is available with rear-wheel drive but not all-wheel drive.

The STS-V comes with a higher level of standard equipment, including EZ Key with remote start, XM Satellite Radio, rear AV jacks, and rear obstacle detection, hand-wrapped leather surfaces with suede seat inserts, Olive Ash Burl wood and aluminum interior accents, rear climate system controls, and V-Series badging. Special paint and a sunroof are the only options.

Safety features that come standard on all models include dual two-stage frontal airbags, front seat mounted side airbags and front-and-rear side curtain airbags. Four-wheel anti-lock brakes are standard. Tire-pressure monitors are available only with the option packages.