I looked into it, you get about $7 or 137 SC per TB per month. This is contingent upon you actually getting a contract though. You also have to put up some SC as collateral to force you to maintain a 99% up time. I think if the price of SC goes up, you could do well but with the current rates, I think you are better off mining elsewhere. Personally I am mining VTC. I get about 1.2 coins a day and am just waiting for it to hit $100 by the end of the year lol.
RE: SIA - HODL or mine?