ROI on these?
at .75 Btc at avg 20% increase and 10 cent KWh
do these ever make the btc back?
.015 BTC per day should ROI in under a 100 days. I already had the PSU's from S1's so no additional costs there. 0.75 BTC is the hairy edge IMO.
NOW where are the COUPONS!!

Id check that math again...They will NOT roi if difficulty increases @ 20%.