WITH higher technology and lower weight, the new, fourth-generation Jaguar XJ poses a more serious threat to the Teutonic luxury car establishment – over which Jaguar claims its new Big Cat represents a sportier proposition., , The supercharged XJs compete on price with Porsche’s Panamera and the Maserati Quattroporte, a car the new Jag also physically resembles from some angles., , If sales of the similarly styled XF are anything to go by, the XJ should continue the renewal of Jaguar's fortunes in Australia., , The task of choosing a luxury car just got harder.