I am afraid this is a relatively easy win for EMS Madara, Rinnegan is not even needed. MS would sap Sasuke and Itachi's strength whilst using Susano'o which they will need while battling Madara. On the other hand, Madara can simply bring out CS, which is bigger than both Itachi and Sasuke's and as he possess EMS, there will be no 'taxing' factor. He can literally sit it out, whilst Sasuke and Itachi climb down from their best reached forms in a couple of minutes.
Most of their attacks will be completely tanked by CS in conjunction with its double swords that took on a point blank TBB from a yin/yang powered Kurama TBB thrown back at him an did not even break. When we are all aware that swords are quite brittle if compared to the compact structure of Susano'o itself.
Obito's five minute Limit can be easily exploited with CS in conjunction with his Madara's Massive Katon attacks and PS can also be brought out to use its slashes with consecutive Katon attacks to make Obito stall. I don't see anyone of these as being a threat to EMS Madara. Add Kurama and Rinnegan into the fray and the balance of power is sharply titled with Madara winning without any effort at all on grounds of Rinnegan's six paths and TBBs.
EMS Madara takes this mid difference max, and EMS + Rinnegan + Kurama Madara takes this zero difference.