Every midsize luxury or sport sedan in existence is compared at some point to the BMW 5 Series. To say it is the benchmark for the class is an understatement. It is the leader, and has been, for about as long as we can remember. Enthusiasts don’t ask if, for example, the Lexus GS 350 is good, they ask if it’s as good as a 5 Series. Maintaining that edge is critically important for BMW, and every element in this set of updates is vital to holding its lead in the battle for hearts and minds of drivers all over the world. On the more practical side, BMW also refines its iDrive system and introduces adaptive cruise control.