It's safe for now, all the exchange platforms are in risk of running , hacking . They have the same chance to be hacked or to run . So my suggestion is to divide your money into several exchanges.
yes i think it's a safe platform to trade cryptocurrencies. i didn't read claims against it and as i saw, everything is smoothly running in it.
Let me point your attention to this thread:
https://bitcointalksearch.org/topic/nova-exchange-community-thread-1606107In August, they added this to their terms:
BETA Notice
Novaexchange is currently in BETA mode in production mode until further notice. The BETA tag will be removed once all known bugs are fixed and no new bugs encountered for a period of 3 weeks. While BETA tag applies things can go wrong and Novaexchange will in timely matter help the user to restore (if any) digital currencies. A trade that has gone wrong can be reversed during 48 hours of the timestamp of the trade and only as long as the currency remain on Novaexchange, once withdrawn or 48 hours has passed that transaction cannot be reversed.
Shortly after, they shut down registrations -- I think they are still shut down for like 2 weeks now. Apparently they have been under attack. This has lead them to ban a wide range of IPs, locking many people out of their accounts.
People are also complaining of withdrawals not coming through. Apparently, email confirmations are not arriving. I urge people to be careful and avoid sending any funds to this exchange until the situation becomes clearer.