The 750i gets a new V-8 engine for 2009 that's smaller but makes more power than the previous engine — 400 horsepower, to be exact. It's the same engine that delighted me in the X6 xDrive50i, and it's quite a performer in the 7 Series, too.

I'm always a little surprised by how quick some big luxury cars, like the Mercedes-Benz S550, can be, and the 750i falls into this category, too. The twin-turbo V-8 offers a wave of power that doesn't quit even when you're already cruising at a good highway clip. It's pretty swift from zero to 60 mph, too, with a time of 5.1 seconds, according to BMW. Unlike the X6, where the V-8's deep exhaust rumble provides all the music you need, you only hear the V-8 now and then in the 750i, when you really get on the gas.

When cruising at highway speeds, the sedan's six-speed automatic transmission is always at the ready for a quick kickdown if you need more power. Plant the gas pedal, and it downshifts immediately. The transmission is smooth enough in city driving — though there was some jerkiness to it at slower speeds right after starting the car on a cold day. If you've driven a car with a manual transmission, it's a mild version of the sensation that occurs when you're not giving the car enough gas and it's about to stall.

The transmission's Sport mode allows the engine to rev higher before shifting, but sometimes it unnecessarily prevents an upshift when one would be preferred. You can also control gear changes yourself using the console gear selector's clutchless-manual mode.

Less impressive are the 750i's brakes, which don't offer the best linearity; sometimes they grab lightly when you first press the pedal, and then respond more strongly. You'd think this would be something BMW could get right on a car that starts at more than $80,000, seeing as much less expensive cars — the Dodge Charger, for instance — have great, firm brake pedals and are easy to bring to a smooth stop.

The cabin is mostly quiet, but there was an ever-present drivetrain whine that became more pronounced as engine speed increased. It's not the greatest of sounds, and it's one that customers likely wouldn't accept if they continually heard it during a test drive, like I did during my time with the car.