Cloud mining *can* turn a profit but the problem with cex is not their hardware or the site itself, it is the site management which likes to jerk around users and change there TOS on a whim. There are several alternatives to cex.io, I hope the new one that is creating a buzz eventually forces cex lower on the scale.
My advice is do not trust cex.io or Jeffrey Smith AT ALL.
What are some viable,
reputable alternatives to CEX?
. You can buy (and sell) hashing power and no one doubts legitimacy of Bitmain.