i like kraken, there is leverage there and other features, bitfinex also seems good, but there was an hacking attempt in the past, the one that is still somehow safe is only kraken to me
I am with this. kraken is pretty safe. even Poloniex is a bigger exchange. but they still don't have proper security. but kraken require you to verify your Identify . proof of address ID card etc. which is a good point for them.