on 17 feb 50btc refunded me for the lost amount. So there is no problem on that end. afterwards i got mail from them stating :

" As you maybe already heard, on 11 of February a massive ddos attack
was made to Bitcoin network
(http://www.coindesk.com/massive-concerted-attack-launched-bitcoin-exchanges/).
As a result of that, some of transaction were made incorrectly. "

So at least on my account, there is nothing indicating that they're scammers.