I'm using CEX.io for 3-4 years. All technical diffuculties was resolved in timely manner.
It is a debatable statement. I wanted to withdraw my crypto, but without any success.
They instructed me that I will receive a confirmation email, but there is nothing in my email account, of course I checked a spam folder.
I wrote message to the support team 3 days ago, but nobody has reached out to me since that.
Actually, I was able to withdraw my BTC. The problem was because my email was being filtered as a spam.