In the right crowd, nevertheless, the GS 450h has some green bragging rights; it comes with a 292-horsepower, 3.5-liter V-6 and an electric motor system, together making 339 hp and powering the rear wheels.
Since the 450h's gasoline engine is so smooth and well-muted, and the transmission never shifts per se, with near-silent boost provided by the hybrid system's electric motors. Speed gathers quickly and often faster than you intend in normal driving. Only in lower-speed stop-and-go will you notice the transitions.
Most of the elements of a good sport sedan are here. The 450h is a few hundred pounds heavier, so it doesn't corner quite as athletically, and as with the rest of the Lexus GS lineup, the steering could use more road feel. Brake coordination could also be a step better in the 450h. And there's one other little packaging difference because of the battery pack: a smaller trunk.
Pounding in the point that this is more of a performance car than a high-mileage hybrid, the 450h is only rated 22/25 by the EPA, and over several drives our editors haven't seen figures close to those; we've seen 18 or 19 in mixed driving--only slightly better than the GS 350.
For more information, see our full review of the 2011 Lexus GS 350, where you'll find more images, related news, and what other review sources have said.