gip comparison

Hey guys just wondering, because the metric for CSG takeovers varies greatly, surely the suitor considers the GIP?

ESG 17 tcf http://www.easternstar.com.au/pdf/broker/ESG_180209.pdf

BOW 13.8 tcf http://www.bowenergy.com.au/company.html

Based on these figures, using ESG's offer of $924m as a constant, BOW could expect $740m or $2.11ps. But then you have the proximity of BOW to Gladdy, presumably less water disposal issues, QLD governance - They should be expecting a premium?

Be interested to hear thoughts or other methods of comparing the two.