Both of the new hybrid E-Class sedans combine a 27-horsepower, 184 pound-feet of torque electric motor with a combustion engine to deliver what Mercedes-Benz claims is the most efficient full-size sedan in the world--at least in the case of the 4.2-liter per 100 kilometer E300 Bluetec Hybrid. That translates to about 56 mpg U.S., though of course our test methods are different.
The E400 hybrid, which uses a 302-horsepower 3.5-liter V-6 gasoline engine, will go on sale in the U.S. in early summer. It gets an adjusted, "U.S.-style" 27 mpg, presumably combined, which indicates a highway fuel economy figure in the low-to-mid 30 mpg range, and a city rating around 23 mpg.
With both cars, the driving experience is still a priority as well as fuel economy, though we'll have to wait until we've been behind the wheel to be the judge of that.