I was playing on GSN a while when I decided to try World Winner.
At first it seemed ok, I won a few, lost a few, kept making small deposits, then I finally won a tournament. I asked to withdraw some funds, and that's when they accuse you of fraud, multiple accounts- etc- same complaints I'm now finding out.
I am not a cheater. My whole family plays there- but we live in different addresses, and only have 1 account per person as their rules state.
BEWARE!