It seems when you withdraw your money for first time from adkinsbet, your withdrawal will be processed by manually. (Up to 72 hours IMO in adkinsbet)
That's not the case of course I think because if I can remember correctly, I had one withdraw which was done within one hour or low. I can't remember exactly but it's no more than hour. So, unless there's no issue with your account, I think the withdrawal is faster.
I think there is hardly anyone who processes payments automatically
Don't BetBTC have instant withdraw? I think they have. Some of the users mentioned in their ANN thread that they had got instantly after clicking the withdraw button.
I'm not quite sure about BetBTC only played on them multiple times. I don't think they would process high amount automatically well for me 72 hours or more is not a problem unless the i withdraw a small amount i think that was different story.