I *successfully*followed the answer to this question to set different sensitivites for my touchpad and my USB mouse. Only problem is, once you unplug and replug the device or shutdown, restart, etc., the settings reset.
According to this entry:
The method for changing the settings on a per-user basis is by using the
The settings should be remembered after you unplug and replug the same device. But if they're not then we have a bug to report. I looked into all the events that happen when input devices are detected and I don't mind telling you that it's a real mess. If you need to go to a plan B. then try adding the options into