A few of my friends got ripped off when transferring ethereum out of coinbase, and coinbase always say they copied and pasted the wrong address, which as you know is impossible to do unless you are half blind or half blind drunk, anyway, I store my crypto keys on a nano s by ledger and recommend them, the thing with all these sites is they want you to show id etc and that is hardly Decentralized , as governments can and will come after tax, their greed knows no bounds, and that is the frustrating part, for me.