Sportsbet is running a signature campaign since July 2018 and has been paying participants including myself since I was part of this signature in September or August , it has been so long I don't remember. I have won many bets and the withdrawals were almos instant. It is my favourite sportsbook since September and although I am an occasional gambler I really love their interface and the vast variety of bets and games it offers.
What I can add is the following: I had small issues in the past with sportsbet, but after getting in touch with the live chat, I always had a promptly and satisfactionary reply that have always resolved my problem. This is definitely something that I appreciate, instead of super fast auto-replies that aren't gonna fix issues.
The live chat is active, so I believe they are outstanding on that area.
In my gambling experience with this site, I never had an issue like withdrawal processing since it's instant, in less than a minute, you can expect to see it in the blockchain. I only contact them to inquire about a certain game or request game/s that should be available, and they entertain this kind of thing, so I'm satisfied.