When it comes to SUVs these days, the economy may be saying "less," but the auto business is saying "more," according to a Wall Street Journal story by Gregory L. White and Joseph B. White. In a collective case of one-upmanship, high-end makers are rolling out models with selling points that sound straight out of Superman's bio. Want speed? The Porsche Cayenne, due out in about six months, will go faster than many sports cars, while BMW's new model hits 60 in six seconds. For the military-minded, the new Mercedes-Benz is built like a troop transport; in fact, it is one. Need pampering? The new Lincoln Navigator has air-conditioned seats and steps that appear automatically when you open the doors. Carmakers are hitting the extremes for a simple reason: Huge and flashy has been hugely popular, with luxury SUV sales up 12 percent so far this year in an otherwise sagging market. But now, manufacturers may find themselves on shaky ground, according to the Journal. With the economy spinning its wheels and Americans sensitive about conspicuous consumption, outlandish models that looked great on the drawing board may not play as well in the suburbs. And more importantly, there's more competition than ever. For their part, automakers are confident people will keep buying these rigs -- in fact, they say they've picked up no sign since last fall that buyers are shying away from ostentatious trucks that often get less than 15 miles a gallon, according to the Journal.