MD3000i with MS iSCSI initiator: MCS or MPIO or both ?

We've been using ESX for years so MS iSCSI initiator is not something I'm very familiar with.  But I know the MD3000i MDSM (manager)  is installing the MPIO drivers to be used through MS iSCSI initiator (integration and it works, no problem here)

I can add the multi path I/O (MPIO) in iSCSI initiator.  All is working fine.  Least queue depth with subset policy is configured as a default policy.  But when I click on MCS I see Round Robin.  

I'm not sure to know which one is used or seen by the MD3000i, I'm a little confused here so I hope someone can help me on that

Thanks