Depends where you are. I use Coinfloor (UK). I've heard good (and nothing bad) about Gemini for US. I also used Kraken in the past but now I actively avoid any

Depends where you are. I use Coinfloor (UK). I've heard good (and nothing bad) about Gemini for US. I also used Kraken in the past but now I actively avoid any exchange which deals in Tether, as they've repeatedly failed to produce an audit to show that the money actually exists.