Hello i have been gambling with not many bitcoins on two sites (satoshi mines and on BetterBets dice game) and i want to deposit £5 on one of the sites, what site should i put it on (you can also list some recommendations for other sites but i like satoshi mines and on BetterBets out of the ones i have testes) 
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BTC BTC BTCBoth of the two sites you mentioned are good. They are both provably fair and have been established for quite some times. Having said that, I would suggest you to try safedice which has a 0.5% house edge while Betterbets has a 1% house edge (though playing on BB has some other benefits like cashback and raffles).