best mouse sensitivity number

[jamz]

There is no definitive, specific answer, since the actual amount moved depends not only on the in-game sensitivity, but the resolution (DPI) of the mouse and any adjustment that the OS is making. Also, you may prefer a lower sensitivity if you want greater accuracy over small distances, or higher sensitivity if you want to aim very quickly with smaller hand movements. Some players play without moving their hands at all, just their fingers, so they have higher sensitivities than those who are happy to move their entire arm over their 2ft² mouse mat.
See if /findsens helps you.