1,292,000 Gh/s will mine us 2.4mil usd cumulative return.
BUT if we sell them out, at cheapest market unit rate, say $3/Gh/s, it will be usd 3,876,000, of course only accept payment in bitcoin to lock the exchange rate risk.
If we sell them out at $6/Gh/s, which is the unit rate of 24Th/s monster, we will have usd 7,800,000 profit.
Of course we can do both, mine btc at first then sell the miners.