It looks to me like 0.051 BTC per GHS not 0.51. At 0.051 ROI has a chance of going positive in the second year. Of course that's dependent on assumptions which are highly subjective person to person. The real curious thing for me is to watch how the price of this will have to drop over time in order to remain viable, at least for people who do somewhat realistic calculations before investing. We've all seen (ebay) places where expectations are completely out of line with reality, so who knows, this may be selling pretty quickly. The other concern with any longer term investment is the stability of the holder. Currently I do not see the risk/reward being high enough to invest in something like this. If there was any chance that I could see a positive ROI in year one, or even doubling of my investment by year four, then it might be worth a small investment. As it is, there is no appeal here other than curiosity, which might get me to buy 1GHS from them, who knows.

I do disagree that this can be compared with cex.io. I think that looking at cex.io as a mining operation is not understanding the commodity market of GHS there. Today, especially one day before another significant difficulty change, I'd be stupid to spend 0.07 BTC for 1GHS, but I think it is reasonable to deposit 0.07 BTC short term for an instantly accruing interest. Long-term I'd be worried about the principle significantly declining in value.