According to Martin Wimpress, Project Lead for Ubuntu MATE, the PPAs use the same source packages that he's done for Debian, which are currently being reviewed by the FTP masters and should land in Debian Unstable in a couple of weeks, so they should be safe to use.

I've never actually needed to modify the mouse scroll wheel speed until recently, when I got a new mouse and I wanted to change the scroll wheel settings. That's when I noticed there's no such option in Unity / GNOME Control Center.

I searched for ways to change this under Linux and the easiest to use seems to be "imwheel", a command line tool that can be used to tweak the mouse wheel behavior and which, among others, can change the scroll speed of the mouse wheel, and I decided to share the information with you.