Unlike some of Lexus' other hybrid models, the HS is tuned to maximize fuel economy, not performance. If you're looking for driving thrills, look elsewhere, but if you genuinely want to burn less gas while still enjoying lots of luxury features, this is your car.
The HS250h gets considerably lower fuel economy than the Toyota Prius -- not that 35 mpg is anything to scoff at -- because it's a much heavier car, requiring more power to move. For that reason, it has a bigger gasoline engine. But it still beats other luxury cars by a wide margin.
The next closest contender in the "upscale" or "luxury" classes is the diesel-powered BMW 335d. It gets 36 mpg on the highway and 27 in the city.
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