Hello to all, as stated in sources articles, the most recommended hierarchy configuration is stand-alone primary. Reasons are exposed in several articles, like here.

    Do you know if there are any new features present in SCCM 2012 R2 that would justify the use of a CAS?

    By your experience, a company with 6k workstations scattered among aprox. 500 sites, cental IT management and no strong fault tolerance for SCCM would demand a CAS?

    Regards, EEOC.

With 6000 clients, definitely do not use CAS. If you'd have more than 100 000 clients, then you could justify the use of CAS, since that's the limit of clients by one primary.

More info:

https://sccmgeekdiary.wordpress.com/2012/08/13/to-cas-or-not-to-cas-that-is-the-question/

 If you'd have more than 100 000 clients, 

It's been increased to 150.000 with R2SP1 or SP2. 

With 6000 clients, definitely do not use CAS. If you'd have more than 100 000 clients, then you could justify the use of CAS, since that's the limit of clients by one primary.

More info:

https://sccmgeekdiary.wordpress.com/2012/08/13/to-cas-or-not-to-cas-that-is-the-question/

• Proposed as answer by Jason SandysMVP 18 hours 38 minutes ago
• Marked as answer by EEOC 17 hours 27 minutes ago

"Do you know if there are any new features present in SCCM 2012 R2 that would justify the use of a CAS?"

A CAS is a CAS is a CAS. Version does not change its role or use within a hierarchy.

You do *NOT* need a CAS or multiple primary sites.