ONE thousand, two hundred and sixty five. That's how many changes Saab has made to its medium-sized luxury 9-5 range in a mid-life update launched here late in 2001. The trouble is most of those changes are completely hidden from view, below a conservative three-box shape that has barely been changed from the original revealed in 1997. Perhaps the most obvious exterior change is to the nomenclature, with 2.0, SE and Griffin all disappearing, replaced by - in ascending order of price - Linear, Vector and Arc. The Aero name, with its sporting connotations, is carried over from the old range to head up the new one. Here we are testing the entry level Linear, powered by the excellent 2.3-litre low-pressure four-cylinder turbo engine. It is mated to one of the new 9-5's 1265 changes - and perhaps its most important - a five-speed automatic gearbox.