THE small to medium luxury European passenger wagon market is a niche within a niche but a smart way for a manufacturer to yield incremental sales. Audi only expects to add 13 per cent to its A4 bottom line but that’s a good 300 cars extra a year that it can sell off the back of a range already established. The Holy Grail for these niche European wagons (which also include the Mercedes-Benz C-class Estate and BMW 3 Series Touring) is the mammoth SUV market. Like its German competitors, the Audi marketing men would like to know how their practical compact luxury wagon could lure away even a fraction of the SUV buyers. Does the A4 Avant have what it takes to steal SUV sales?