Just wanted to confirm that v18.xx package change works. I had issues with v17.xx where I couldn't successfully change the driver package, but perhaps v18.xx with Xorg works? I don't know why, but it does:

If you have mouse/trackpad speed issues, try adding and removing the packages mentioned in this post:

https://bugs.launchpad.net/ubuntu/+sour ... ug/1682193

Second last post...add one package and remove the other IN THAT ORDER.
DO NOT REMOVE FIRST or you will be left with no mouse/keyboard driver...you can work around it, but so much simpler to to just add first then remove.

So far so good...I'm still using v16.04 still for my main desktop, but will update to 18.04 now that I'm fairly confident of how to fix my "simple" mouse speed issue. This is something Ubuntu/Kubuntu need to address...I can see many non-technical users getting pee'd off over such a simple driver issue and never using Ubuntu-based OS's again. Sad but true...something I've been struggling with for months and this seems to work now.

C'mon Kubuntu team, is this really something you want to ignore?