The first isMouse Speed Switcher, a simple utility that allows for multiple input devices and multiple prefs.

Mouse Speed Switcher supports hotkeys, too.

On the other hand, its free and doesnt nag you.

How To Set Different Speeds for Your Trackpad and External Mouse

Personally, I use Autosensitivity and Ive had no real issues.

AutoHotKey Script

What if youve only got one gear but want to switch between two sensitivities quickly?

Sounds like a job for AHK!

MouseSpeedSwitcher

Heres a simple script that will do what you want quickly.

The important values are the UInt values here, the third number in each row.

How did we get those numbers?

autosensitivity

The value of the first one is 0, and the others add 2 points to the score.

My touchpad setting from the screenshot is on the eighth notch, which is a value of 14.

Mouse Sensitivity AHK Script and Executable Files

mouse_pointer_options