why bother pay 14.9 BTC for these when they can only produce like 9-10 BTC ?
So I take it you have a magic crystal ball too?
Mine says these can easily break even with cheap electricity.
He's right, if you pay for electricity, no roi
Average diff increase for last 10 changes is 12%. Put that into any decent calculator, it will tell you that 14TH/s can mint about 23btc.
BTW, 12% increase is 64'000 PH/s on next halving. Just electricity cost per day for this (at 0.3 kWh/TH, and $0.05/kWh) is $23'000'000. Bitcoin at $6000 in 2016! I like that.