Honestly, there are so many casinos that it's hard to get oriented which one is good or bad. From my own experience, most of complaints and voided winnings are based on breached bonus terms and conditions. It's absolutely crucial to read terms and conditions whenever you play with a bonus.
I'd also never play for too much money in a new casino. I'd rather try to withdraw even very small winnings just in order to see how the withdrawal process goes, if there are any issues with my verification etc. When the first withdrawal is complete with no issues, then I wouldn't be too afraid of not getting the winnings.
But in case there are issues and you feel something isn't right, then even if you get your money after few weeks, I'd run away from the casino.
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