First, the 325i and 323 models are BMW's premium touring cars, focusing on comfort.

Secondly, m3 and m6 are luxury cars improved by BMW on the basis of f 1 racing car, focusing on sports. Its gearbox is the original gearbox of f 1, which has a loud shift noise, obvious feeling, short engine maintenance cycle and high maintenance cost. It is a word to drive-fast! Comply with the design concept of f 1, and pursue speed regardless of cost (regardless of engine life).

M series is different from 3 series, with strong power and fast speed.

Generally, the shift speed of 1 and M series is much higher than that of 3 series. This can refer to sports cars.

2. Because of the high speed, the M series adopts a pre-tightening braking system, which you can understand as a pre-tightening contraction as soon as the accelerator brake is released.

3, m is a maintenance every 2000 kilometers, haha.