When it comes to discreet efficiency, few cars can rival the Audi A4. Whether you want a saloon, estate or a cabrio­let, it’s more than up to the job. The A4 is the perfect choice if you’re looking for a classy and luxurious compact executive machine. It’s seriously capable – especially when equipped with Audi’s famed quattro four-wheel-drive transmission. Strong residual values mean it’s hard to find a bargain, but the A4 is better value used than its Mercedes C-Class and BMW 3-Series rivals.HistoryThe second-generation A4 was launched in December 2000 as a saloon. The Avant estate followed in July 2001, coinciding with the first 2.4-litre petrol and 2.5 TDI diesel engines. In May 2001, 100bhp and 115bhp versions of the 1.9 TDI joined the existing 130bhp model. A 2.0-litre FSI petrol arrived in July 2002.The big news was a major facelift in September 2004, which included fresh front and rear styling, plus additional engines. These comprised the 2.0T and 3.2 V6 petrol units, plus 2.0 and 3.0 TDI diesels.