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The usual Tiptronic-type selector lever and steering-wheel paddles are carried over to this S-tronic, and you drive it in just the same way. It behaves very much like a sportingly-programmed torque-converter auto such as a Jaguar's ZF, with a solid, mechanical drive once moving just as in that ZF whose converter stays locked once under way. The shifts are smooth, down or up, helped by the usual well-judged throttle-blip when needed. Seventh gear gives very relaxed cruising; the ratio spread between first and seventh is eight-to-one. Unlike an epicyclic gear train as used in torque-converter autos, in which mathematics dictate what the ratios of the interconnected gears have to be, the S-tronic can have ratios tailored exactly to the car's needs.

Sport mode speeds the shifts (to 100 milliseconds from 200), livens up the kickdown and locks out seventh gear. Manual mode feels near-instant and of course there's the impression of a continuous torque delivery during the shift. Our prototype test car had an occasional slight snatch when shifting but Michael Schöffman, Head of Geared Automatic Transmission, says that will be fixed with the final production calibration before sales start in the summer.