15 BTC with units shipping now is clearly profitable:
http://mining.thegenesisblock.com/a/44fc645248 (55% month-over-month difficulty increase), and even a pessimistic
100% month-over-month increase is profitable. Also,
15 BTC for 105 Ghash/sec beats the price per Ghash/sec of any competitor shipping now or in October!
1) You can't buy them for 15BTC right now. 19BTC is a little less optimistic.
2) You have the Initial Mining Date as September '13. You change that to October '13 (cuz Sept is basically over), and all the numbers go red. As in no profit. Am I looking at this wrong?