Among the many charms of the Audi R8 Spyder is its embrace of the exclamation mark. Press the button below the new seven-speed S tronic transmission’s gearshift lever, and the instrument panel proclaims, “Sport mode on!” Press it again, and the car responds with similar enthusiasm for “…off!” Appropriate sentiments, both of them, as in either mode the gearbox represents a significant upgrade for a car that was nearly perfect already.