The Impala's 3.9-liter V6 delivers responsive performance and manages 20 mpg overall but sounds coarse. The optional V8 is quick but spins the front tires too easily. Handling is sound, but body lean is noticeable. The ride is absorbent but unsettled. The cabin is fairly quiet, but wind noise is pronounced on the highway. Controls are easy to use. The front seats are comfortable; the rear seat is unimpressive for such a large car. Head-protecting curtain air bags are standard, and ESC is optional for 2008. Reliability of the V6 is average, but the V8 is well below average.