Changing SETs as part of declaritive sync model

I'm still in the Dev lab and have had a SET with all users for my initial Outbound Sync rules.  I need to start filering the Sync rules and will be replacing  the ALL Users set.   I changed my existing MPRs for Add user \ Remove users.  But, I did not see any difference in the accounts that were created in the target.

Is the any dependency I missed when change the SET?

Thanks, Stu