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.
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!
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?
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