The Irbis-E of the Su 35BM is not an AESA radar but a PESA, it is a further developed version of the BARS that the MKI already has. The radars on offer for the upgrade are Zhuk AE like you mentioned, but also an AESA upgrade of the BARS. By logic, the upgrade of BARS seems the best choice, because we already have nearly a decade experience with that radar and an upgrade could be more cost-effective. On the other side it is clear, that sooner or later the IN Mig 29K / KUBs will get Zhuk AE as well, that means getting a single radar for both forces would give logistical advantages too.
Another point could be important is, that Bars and Irbis-E were developed by Tikhomirov NIIP, just like the radars for Pak Fa / FGFA, which means they are highly capable and the future comitment of Russia is clear as well. Zhuk AE on the other side is developed by NIIR Phazotron and although they should be very capable as well, we heared about finacial problems during the upgrade negotioations of Mig 29SMT and possible delays in the Zhuk ME radar production. Russia will not buy more Mig 29s, except those Mig 29Ks as a stop gap till their new carriers with naval Pak Fa's will be ready. But India is already the biggest customer of Mig 29s with Zhuk ME radars, so the future potential might be dependent on our fundings and we all know that this a perfect situation for delays and later cost rises.
Both companies will offer a radar to IAF and only they can compare the capabilities of them and their developing companies, so lets wait and see what they decide.