There are four models in the BMW 5 series: the 525i Sedan (from $43,500), the 530i Sedan (from $47,500), the 530xi Sports Wagon (from $52,100), and the 550i Sedan (from $58,500).

The 525i opens the series with a 215 hp, 3-liter engine delivering a pleasingly smooth level of performance without compromising on the vehicle's essential power. The spacious interior is an enhancement for 2007 that augments an overall boost in high-tech handling and comprehensive occupant safety features. The move up to the 530i means a bump to 255 hp in the standard three-liter engine (an inline six), which also offers double valve timing. Consequently the 530i is just a shade more agile than its relatively smaller sibling.

The big brother of the series is the 530xi Sports Wagon. You're still working with a 255 hp, three cylinder but you're gaining a lot of cargo space and truly stout all-wheel drive capability. A real selling point is the presence of Dynamic Stability Control, which is but one of a thorough suite of safety features that make this wagon steady and stable without giving up on its capacity to carry you and your family to fun and exciting destinations - regardless of the weather and the road conditions along the way.

If the sports wagon is the big brother, the 550i sedan is the elder statesman of the series. Even lounging in the garage this BMW exudes power, with good reason. Look under the hood and you'll find a 360 hp, 4.8-liter, V8 waiting to wake up and purr like a lion. Expect some modern bells and whistles on this big guy including one button start and stop, a higher level of DSC, brake drying, assist function for hills, and soft stop capability. You'd have to be a pretty picky driver to find the 550i lacking in luxurious amenities and forward-thinking engineering.