MT Exchange 2013 and Public Folder Limits

Question

So having some real trouble trying to digest this data from a multi-tenant perspective. 
Total public folders in hierarchy
10,000
Although you can create more than 10,000 public folders, it isn’t supported. Create
a Public Folder
Sub-folders under the parent folder
10,000
Although you can create more than 10,000 sub-folders under a parent folder, it isn’t supported.FolderHierarchyChildrenCountReceiveQuota parameter on the Set-Mailbox cmdlet.
So if my hierarchy consists of root folders 0-9,A-Z.  Then below those top levels I place tenant domain level folders.  Then below that I actually have folders for tenant data.  Which of the above category applies?  Sub-folders under
the parent folder is somewhat misleading?  Does that mean in my above scenario I would only have 36 "parent" folders then would be able to have a total of 10k subfolders under those parents?
Or does it effectively mean 10k folders, that is all.  One parent folder and 9,999 sub-folders?  Or some combination of the two?
I had very high expectations for the redesigned public folders with incorporation into the DAG, but this solution seems MUCH less scalable and flexible then the legacy design.  Additionally the recommendation of 2k concurrent users per PF mailbox, with
a max number of PF mailboxes at 100 effectively sets an org limit of 200k total mailboxes.
I can't help but feel this is just another nail in the coffin of non O365 Exchange resellers.

Answer 1

Hi,
Based on my research,  the public folder size can be up to 100GB in the hosted Exchange 2013 environment:
http://www.wisnet.com/blog/hosted-exchange-2013-is-available-now/
As long as the total number is beyond the limit, we can at most have 100 public folder mailboxes ,10k public folders, 10k subfolders under one public folder and 200 concurrent users for one public folder mailboxes.
For more information about the public folders in Exchange 2013, you can refer to the following articles:
Public folders
 http://technet.microsoft.com/en-us/library/jj150538(v=exchg.150).aspx
FAQ: Public Folders
http://technet.microsoft.com/en-us/library/jj552408.aspx
Public folders in the new Office
http://blogs.technet.com/b/exchange/archive/2012/11/08/public-folders-in-the-new-office.aspx
Exchange 2013 Modern Public Folders
http://windowsitpro.com/blog/exchange-2013-modern-public-folders
Public Folder Hierarchy and PF Mailboxes for Hosted setup
http://social.technet.microsoft.com/Forums/exchange/en-US/e9062abe-f484-462b-bc5e-ebdcb0862760/public-folder-hierarchy-and-pf-mailboxes-for-hosted-setup 
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thanks,
Angela Shi
TechNet Community Support