There is an app in Ubuntu repository KDE system settings. In KDE I saw the customization of hardwares and removable devices can be done pretty precisely. I was wondering If I can use the KDE system settings in Unity to customize the removable devices like the Wacom or the mouse etc. I have no complaint about Unity's other system settings. just KDE's Wacom, mouse and monitor settings have many options to configure them accurately. So possible to make KDE system settings work in unity in that purpose?

If Yes, then how? Just normally install and use it? or I will need to replace the Gnome system settings somehow?

Ubuntu 12.04 LTS Unity

I'm not sure what will happen in this case - as part of the KDE startup process usually involves applying these "system settings" (although there is no universal mechanism for this, so I am not sure how the wacom tablet works).

At worst you would need to reopen the KDE System Settings application and make a small tweak to your settings so that they are reapplied by it.
The application should otherwise work under Unity however.