More than 30 sport utility vehicles have a safety feature called electronic stability control, which makes SUVs less likely to slide or skid, possibly preventing a rollover. But Consumer Reports says some stability control systems are not foolproof.

"Stability control actually senses when the car begins to slide sideways. It then applies a brake to one or more wheels, which causes a rotation in the opposite direction, bringing the car back under control," said Consumer Reports' tester David Champion.

At Consumer Reports' test track, engineers test all their vehicles -- including SUVs -- through a series of tests to see how well they handle in emergency maneuvers. One test assesses how well the vehicle corners at increasingly higher speeds. The engineers evaluate how well the vehicle handles sharp curves. And another test checks how the vehicle handles if the driver has to make a sudden abrupt turn.

In Consumer Reports' latest tests, some SUVs earned a poor score for emergency handling, even if they had the stability control.

While the 2003 BMW X5 3.0 did well in most handling tests, it did have a problem, according to Consumer Reports' officials. They said the vehicle experienced a moderate tip-up twice on an emergency-handling course.

The 2003 Mitsubishi Montero was generally clumsy in handling, according to officials. They said its electronic stability control did not prevent a moderate tip-up on one of its runs, while using outriggers to protect the driver.

Other SUVs with stability control did better in the emergency handling tests. But Consumer Reports found there was room for improvement with the Acura MDX and the Subaru Outback VDC.

"Stability control in theory works very well. But some manufacturers allow the car to slide too much before applying the brakes. We like the more aggressive systems that actually put the brakes on as it begins to slide, brings you under control quicker," Champion said.

But Consumer Reports said even though stability control is not a cure-all, it does improve handling and is a safety feature worth getting.

Consumer Reports' tests show that many SUVs do effectively use stability control, including the Audi Allroad, Infiniti FX, Lexus RX 330, Nissan Murano, Volvo XC 90 and the Toyota 4-Runner, Land Cruiser and Sequoia.