Were aware of the ICO scams on C-CEX. I even fell for one there before Christmas. But I never blamed the exchange. As long as the exchange is secure and honest it should be ok. And investors can move their coins to a NXT wallet right away if they are nervous about it.
The thing I don't like about C-CEX is when it removes a coin it doesn't give its customers long to withdraw their balances before it claims them for itself.