Women are the biggest SUV buyers because of the relative safety of the big vehicles, said Diane Steed, president of the Coalition for Vehicle Choice.

"They're safe, they're high off the road and they're good vehicles," said Cal Thomas, a syndicated columnist and SUV owner.

But critics say that not only are SUVs not safer -- they are more likely to roll over than smaller cars -- they are much less friendly to the environment, sucking up large amounts of gas and spewing high levels of pollutants. Critics also say the size that makes SUVs safe for their drivers can make them a menace to other cars on the road.

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