With a supercharged V6 engine ... with the 540i xDrive's 20 mpg city and 29 mpg highway numbers but betters the E43's 18 mpg city and 25 mpg highway figures. The XF's sheetmetal is an evolutionary ...

Mercedes fans are going to cry foul on this one, but we've often wondered how last year's E43 and its twin-turbo V6 compares to the all-new M550i, which BMW dropped a V8 into. We do agree that not ...