@CoolAsh bhai, this might sound absurd, but my sense is that bull markets thrive with recency bias. They may give a premium to a newer listing, even if it is smaller. Further, if something is undervalued, it may remain undervalued way beyond logic and reason. Or our understanding of its valuation may also be flawed. As they say, markets may remain irrational for longer than we are solvent! End of the day, bhaav bhagwan chhe (price is the only truth), rest are theories and fantasies!
I also feel MGL deserves a look-in, but I already have some exposure to it since its IPO, and added a bit in last week's crack too. Generally, market does give a premium to pvt sector over public sector. Whether MGL will outperform IRM or not is anybody's guess.