Toyota Motor Corp. is getting pretty good at this hybrid thing.

When consumers complained that the first-generation Prius hybrid/electric vehicle suffered from power surges, engineers smoothed out the delivery of torque.

When critics said hybrids still lacked punch, Toyota boosted displacement with a V-6 for its Lexus RX 400h and Toyota Highlander hybrid cross/utility vehicles.

The RX 400h is good, but remains lacking. Step on the gas at a stop light, and the engine sputters to life with an air of hesitation that undermines its luxury roots.

Toyota engineers have put these concerns to rest with the new Lexus GS 450h hybrid sport sedan. This performance-oriented HEV trumps all current hybrids, catering to well-heeled buyers while being as quick as a Porsche 911, Lexus says.

A 911 with automatic transmission dashes to 60 mph (97 km/h) in 5.2 seconds, which is the same 0-60 time achieved by the GS 450h, Lexus says.

The portly GS hybrid has a curb weight of 4,134 lbs. (1,875 kg), compared with 3,164 lbs. (1,435 kg) for the lithe 911. Clearly, pitting these diametrically opposed vehicles against one another is like suggesting Mike Tyson fight Sugar Ray Leonard.

No one will cross-shop a 911 with a GS 450h. But Lexus makes a valid point. Its sedan is practical, stylish and fuel-efficient — and it kicks butt, too. No, the GS 450h does not sound like a 911 or leap with accelerative glee at the touch of the throttle.

But for a big sedan lugging 40 nickel-metal hydride battery modules, the GS hybrid is enormously gratifying to drive and remarkably well composed.

During test drives, Toyota Executive Engineer David Hermance declared the GS 450h “the best hybrid yet” and challenged journalists to identify the point at which the engine kicks on during acceleration.

From a standstill, a permanent-magnet motor generator drives the rear wheels, and the V-6 springs to life at varying times, depending on the driver's motivation.

But the electric portion of this latest iteration of Hybrid Synergy Drive should not overshadow the capable new 3.5L V-6.

This DOHC mill, recently earning a Ward's 10 Best Engines award, has two injectors per cylinder (one port, one direct).

Combined, the parallel hybrid system produces a whopping 339 hp, trumping the output of certain 911 models, by the way.

Despite its power, the GS 450h upholds Lexus' ultra-refined brand image. In accepting Hermance's challenge, journalists struggled to detect when the V-6 was churning, or merely along for the ride.

Helping the cause is a continuously variable transmission that is so smooth it could make believers out of CVT critics.

At the beginning of our drive, the GS 450h's fuel economy was awful, achieving a mere 18 mpg (13 L/100 km), according to the onboard computer, during moderately aggressive driving. With a tender foot, we achieved 24.4 mpg (9.6 L/100 km), which remains a far cry from the combined 28 mpg (8.3 L/100 km) Lexus says to expect in the GS 450h.

This is getting to be old hat — complaining that an HEV's fuel economy is not living up to its billing. If a car must be babied to come close to its rated 28 mpg, then what's the point of giving it 339 hp?

The thrill of a 911 is appreciating its accelerative means and applying them when prudent. Buyers of the GS 450h, filled with environmental guilt, will want fuel economy, not 911 titillation.

Lexus knows the market for this car will be small. The company plans to sell fewer than 2,000 in the U.S. and 6,000 worldwide annually.

Given its Toyota DNA, the GS 450h somehow will find an audience. The GS 450h begins the era of hybrids with attitude — cars with expressive, sexy lines and even brute strength.

Pricing will be announced closer to its spring arrival. Lexus says the car likely will be more expensive than a V-8-powered GS 430, which has a base price $51,375.