Any of the reputable sportsbook that have a open ANN thread in this section is safe, or at least as safe as it gets when it comes to a sportsbooks that accepts cryptocurrency as payment.

Among the ones that I personally had experience with more than a couple of times I can suggest Betnomi as it worked as intended and they paid the winnings after a match almost right a way and there was no issue that is considerable along the way, one other one that I might give it a try soon is Stake since I'm hearing good things about it but then I haven't tried it myself yet so can't say for sure.

My suggestion is to just go through sportsbooks that have a topic in this section and read other members comment/reviews and decide for yourself if they are worth a try.