I bought an S1 AntMiner in December 2013, and one in January of 2014. Total cost for the 2 S1 AntMiners was 5.35 BTC.
Here were are in June of 2014, and I'm looking at a wallet balance of about 6.6 BTC.
Net profit = 1.25 BTC, or (1.25/5.35 invested)*100 = 23.36-ish %.
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You are right, I did miscalculate my power costs.
700 W for 2 antminers (measured using KillOwatt meter), 24 hours a day, that's 16800 W or 16.8 KW.
At $ 0.10 / KW, that's $1.68/day * 180 days = $302.8 for half a year.
Subtract that from the profit, and that knocks it down to roughly 11% profit.
Still, profit is profit. You're not getting 11% by investing in treasury bills, and AntMiners are way safer than the stock market (Nothing exciting happens in my basement, heh).
Those Antminers are still running, and will be profitable until roughly October/2014.
Thank you for pointing that out.
You're not profitable. At least not if your using USD.
BTC Cost: 5.35BTC*$900 = $4800 (Average of December and January BTC prices)
Power Cost: $300
Current Value: 6.6*$650 = $4290
Profit/Loss: -$810
That's better than if you had bought BTC and held it.
BTC Cost: 5.35*$900 = $4800
Current Value: 5.35*$650 = $3477
Profit/Loss: -$1323
But what if instead you had split that $4800 over 6 months and just bought straight BTC(dollar cost averaging)?
(Buying .892 BTC at the beginning of every month for 6 months beginning in December)
Cost: $1000*.892 + $800*.892 + $800*.892 + $550*.892 + $450*.892 + $450*.892 = $3612
Current Value: $3487
Profit/Loss: -$125
That's better than the $800 loss from mining. But an ever better situation is if you bought at a low point like April.
Cost: $4800 = 13.71BTC @ $350
Current Value: $8914
Profit: $4114
With mining, you're accepting a loss out of the gate and hoping that at some point in the future you can not only make back what you paid for the hardware but also make a profit. In other words, your hoping that:
1. BTC prices don't drop.
2. Difficulty doesn't increase to the point that renders your hardware unprofitable to run before you reach break-even.
With buying BTC, you just hope the price goes up. In addition, you can employ various investing strategies (such as dollar cost averaging) to reduce losses and improve profits. And unlike mining, if the market starts plummeting you can just cash out.
Better for small timers to just buy BTC or set up a regular investment strategy than to mine.