Anyway, among the 3 casino you mentioned, I only tried 2 of them but I only stick on Stake. I agree that Stake has a fast withdrawal, while their customer support are sometimes delayed, and then I only find their UI is quite normal.
Kind of, but they will definitely respond to you before 20 minutes of waiting time; sometimes it doesn't get that long. And what you must know is that stake has a lot of customers, and the support is also responding to other customers. If you send a complaint, you should know you are in a queue. The possibility of getting a quick response is determined by the number of customers being attended to and your number on the queue, which is not usually disclosed.