It appears that the ROI on all the mines has increased. It's now over 6 months to get ROI, instead of the 4 months that it was. Still a good deal, but not as good as it was.  And the prices in US $ are really not correct; for example, level 5 says 72,000 production = about $30.89 per month, but is only really about $21.25 per month at today`s preev.