2003 Infiniti FX35, 2004 Lexus RX 330, 2003 Mercedes-Benz ML350

If today's streets are any indication, you've got the wrong best friend. We're not talking about your dog here: Americans are making happy homes for Land Rovers and other sport/utility vehicles to the tune of 2.5 million SUV sales per year--and growing.

Luxury vehicles and SUVs were once considered separate breeds: one parked in the garage, the other banished to the back stoop for having muddy paws. SUVs simply didn't tread in the plush, cut-pile world of luxury cars. But that changed big time once carmakers figured out how much tail-waggin' profit was to be realized by selling luxury-branded SUVs. Soon nearly everyone was off to the dog races.

What started as the exclusive territory of the Range Rover soon became the well-traveled domain of the Acura MDX, BMW X5, Infiniti QX4, Lexus RX 300, Mercedes-Benz M-Class, Lincoln Navigator, Cadillac Escalade, Volvo XC90, and, recently, Porsche Cayenne. Today, a fast-growing sweet spot is the entry-level luxury segment, with all the major luxury brands counting on SUV sales to help make them leader of the pack.

How much is that doggie in the window? The three entry-level luxury SUVs gathered here--the Infiniti FX35, Lexus RX 330, and Mercedes-Benz ML350--start in the $34,000-$36,000 range, the fat part of the transaction-price bell curve. Yet as testament to just how diverse and varied SUVs have become, each of these players sports a behavior set all its own. We unleashed all three and let the fur fly.