Haha...I wouldn't single out any of them because the end of the day it is money we're talking about. And don't forget Cryptos can be bought to in s much as Fiat has a quality of being difficult to get. If it's your money then it's your money  That's how i see it. Coz using $100 worth of BTC for betting wouldn't be any different from using same $100 in Fiat.