I am looking for example of usage of Samba 4 in real offices (and also Offices with 100 or more users, several sites).I have been browsing the Internet for several days but I cannot find any user case, migration example (neither from Samba4 or to Samba4).I have no real doubts of the capacity of Samba 4 to handle heaps of users but still I really get more user cases 
User case for Samba 4.X
samba;testing;samba4