VMM and SCCM database coexistence

Greetings -

I am in the process of implementing VMM 2012 R2 and SCCM 2012 to work with our new Hyper-V cluster. My initial plan was to create a VM for each app and connect them to a common SQL server. However, I found an article on System Center coexistence (https://technet.microsoft.com/en-us/library/jj851033.aspx?f=255&MSPPError=-2147217396) which indicates that you cannot install the SCCM and VMM databases on the same server.

I can't se creating a SQL server for each component, so has anyone who has done this had any problems or know why MS would say not to install the DB's on the same server?

Thanks.

Carl