Jeff Sabatini (finally) takes a look at the real mileage performance of Toyota’s latest hybrid: The $50K RX400h:

Certainly, it is the Prius’s above-average fuel economy that Toyota has to thank for its image as a green car company. Environmental advocates do not proclaim the righteousness of all things Toyota based on the 958,888 light trucks and S.U.V.’s that it sold in the United States last year, fully 47 percent of its total sales. By comparison, only 53,991 Priuses were sold in 2004, though the company has stated that it plans to double that number this year.
It is understandable that Toyota would like to transfer the Prius’s hybrid chic and green patina to other products. To this end, a hybrid version of the Toyota Highlander S.U.V. was also introduced this year, and the automaker has announced plans to add both a hybrid version of its Camry, the nation’s best-selling sedan, and a hybrid Lexus GS sport sedan next year. Whether these vehicles will be gas misers like the Prius or thirstier performance-oriented hybrids like the RX 400h remains to be seen.
My first seat time in the Lexus hybrid came over a weekend in which I drove the 200 miles from Chicago to Grand Rapids, Mich. I spent a lot of time on the freeway, but I also traveled some back roads and slogged through a couple of stop-and-go city stints. By the time I returned to Chicago, I had put 531 miles on the odometer and calculated my fuel economy at 20.9 m.p.g.