Even with the $50 discount for full members these will probably never ROI at the price you are asking.
http://i.imgur.com/GRG41uX.pngThe calculation above assumes you pay nothing in electricity, the difficulty will never rise, you pay no additional costs for the Power Supply, cables, etc. and I included the $50 price cut in the initial cost. Even with all of those perfect mining conditions (which lets be honest will never happen for anybody) it would take a year to make your money back in LTC.
yes , you maybe right at the this calculation at the current LTC price .
but there are many other scrypt alt coins we can mine with it , if we choose the right coins and sell at right time ,it will no need that long time for ROI.
and for now silverfish is one of the good choice for cost effective scrypt miner .
