DRV8850: 4x IN DRV8850 vs 2x IN DRV8870

Hi Ti experts,

• Why does DRV8850 have 4x input pin to control H bridge. Correspondingly, the DRV8870 has only 2x input. 
• What are the application scenarios of the four inputs.
• In DRV8850 datasheet as below, We can see that DRV8850 has one more High-side slow mode compared with DRV8870. Is this mode have more advantages compared with low-side slow mode.