The 2011 Lexus GS 450h isn't your typical hybrid. Sure, it's got a gasoline engine that runs in concert with supplemental electric motors, but that's really where the similarities end. On its own, the 3.5-liter V6 under the hood makes 292 horsepower. The electric motors boost total output to 340 hp. With this kind of power on tap, it's clear that this hybrid is geared more toward increasing performance than reducing fuel consumption.

By itself, fuel economy is still pretty respectable at an EPA-estimated 23 mpg for combined city and highway mileage. By comparison, the conventionally powered GS 350 achieves 22 mpg and trails the GS 450h in acceleration. The V8-powered GS 460 is also slower to 60 mph by a few tenths of a second, and averages only 20 mpg. Taking all of this into account, the 2011 Lexus GS 450h seems like the smart choice between its gas-only powered brethren -- at least until you consider the price.

Selecting the hybrid GS 450 will set you back an additional $12,000 over the GS 350 and $3,500 over the GS 460. For owners driving 15,000 miles annually and who purchase premium fuel at $3 a gallon, it would take about 57 years to recoup the GS 450's higher price over the GS 350 and about 11 years to recoup the price differential to the GS 460. So if the bottom line is the sole motivator drawing you to the GS 450h, perhaps you should look elsewhere. As a luxury sedan with spirited acceleration, the GS 450h is an admirable choice without a fuel economy penalty.

There are alternatives, however. You might check out the 2011 Lexus HS 250h or the 2011 Lincoln MKZ Hybrid; both are much more fuel-efficient as well as less expensive, but neither is as sporty or prestigious as the GS. On the other hand, the diesel-powered 2011 BMW 335d and 2011 Mercedes-Benz E350 Bluetec both provide a decent amount of power with even better fuel economy than the GS 450h. But as far as hybrid luxury sport sedans go, the 2011 Lexus GS 450h is the only game in town, at least until the BMW Active Hybrids hit the roads.

The 2011 Lexus GS 450h is a midsize, hybrid-powered luxury sport sedan offered in a single well-equipped trim level. Standard features include 18-inch alloy wheels, performance tires, an adaptive variable suspension, front and rear parking sensors, automatic and adaptive xenon headlights, a sunroof, keyless ignition/entry, leather upholstery, 10-way power front seats with memory, heated and ventilated front seats, dual-zone automatic climate control, a power tilt-and-telescoping steering wheel trimmed in wood and leather, a power rear sunshade, auto-dimming mirrors, a rearview camera, Bluetooth phone and audio connectivity, Safety Connect telematics service and a 10-speaker audio system with six-CD changer, satellite radio and iPod interface.

Optional is a hard-drive navigation system with real-time traffic, voice control and Lexus Enform enhanced telematics features. Other options include a rear spoiler, run-flat tires, an advanced suspension (requires run-flat tires), adaptive cruise control (includes Pre-Collision system) and a 14-speaker Mark Levinson surround-sound stereo.

The 2011 Lexus GS 450h is powered by a combination of a 3.5-liter V6 engine and two high-output electric motors that combine to generate up to 340 hp. A continuously variable transmission (CVT) directs power to the rear wheels. Like other full hybrids, the GS 450h can launch and operate at low speeds for a limited distance under electric power only, and then seamlessly engage the V6 when more motivation is needed. Performance is impressive in either mode, with abundant power reserves that we're more accustomed to experiencing in V8-powered sedans.

Lexus estimates the GS 450h will accelerate from zero to 60 mph in 5.2 seconds, which is quick even for a V8-powered midsize luxury sedan. Its EPA-estimated fuel economy is better than average for a V6-powered midsize luxury sedan at 22 mpg city/25 mpg highway and 23 mpg combined.

Standard safety features on the 2011 Lexus GS 450h include antilock brakes with brake assist, traction control, stability control, front and rear side-impact airbags, front knee airbags, side curtain airbags and active front head restraints. Safety Connect, a traditional telematics service with automatic collision notification, stolen vehicle locator and emergency assistance button, is also standard. Adding the optional adaptive cruise control includes a pre-collision system that detects impending collisions and responds by pre-tensioning the seatbelts and activating brake assist.

The GS 450h has not been rated using the government's new, more strenuous 2011 crash testing procedures. The Insurance Institute for Highway Safety awarded the GS 450h its highest rating of "Good" for both frontal-offset and side-impact collisions.

Whether cruising on the highway or carving through turns, the 2011 Lexus GS 450h seems well suited to a variety of driving styles. The standard adaptive variable suspension serves up a smooth, soft ride in Comfort mode, yet has the ability to provide stiffer and more responsive dynamics in Sport mode. For more spirited drivers, the optional Active Power Stabilizer significantly reduces body roll when cornering. The regenerative braking system tends to react a bit too aggressively for uninitiated drivers, but after some time behind the wheel, we acclimated and easily achieved quick and confident stops.

Upholding the reputation Lexus has for finely crafted interiors, the 2011 GS 450h's cabin surrounds occupants with supple leather and rich wood and aluminum trim. Average-size adults will fit comfortably, but taller passengers may desire a bit more headroom -- at least compared to other sedans in this class. This is especially true for those relegated to the center rear seat, which is slightly elevated compared to the outboard seats.

Our gripes are minor and include less-than-intuitive audio controls and a distracting glare from the highly polished wood trim. The GS reclaims some points for its optional high-resolution touchscreen and easy-to-operate navigation system.

Some trunk space had to be sacrificed for the hybrid battery, with the GS 450h accommodating only 10.6 cubic feet of luggage compared to 15 cubes for the conventionally powered GS models.