App for remembering different mouses' tracking speeds?
According to this article, Steermouse will allow you to save different profiles on the mouses (among other things).

Build Profiles
One of the best features of Steermouse is the ability
to have multiple profiles. This works well if you have multiple people
using a mouse that all prefer different settings, if you have more
than once mouse that you use on a regular basis, or if you would
prefer to use different mouse settings for different tasks, workflows,
games, etc.