The ROI on a 3xx Mh unit is 6 months, but in 6 months the DIFF level will turn the ROI into 2 years, who pays $260 for these things?
I just wish I thought of this because they are making millions and in exactly 30 days people are going to be screaming because they realize they will like never get their money back.
When they can be had for $70 let me know
Go do the math and figure out when exactly they become 'unprofitable' to run at 1.5 Watt!
Sure they are not cheap, but considering that I can run 1 of them for 800 hours for $0.05 they will continue paying for themselves for years even with crazy diff increase, and that is not accounting for possible (probable) increase in bitcoin value. + You get a kick-ass conversation starter and a piece of history!
I did the math, using cost of electricity at ZERO, and the cost of the Miner at 2 BTC you will get your money back in 172 days if the DIFF does not change.
If the diff goes up at the anticpated rate, you will get your money back in over a year.
If you took those same two BTC and added 1 more BTC and bought a 5GH unit from BFL and they took 4 months to get it to you, you would still get your money back faster.