There is outside threats like hacking to, like 2 other sites have happend to them.
I think Just-Dice owner dooglus can be trusted alot, he held 50k btc as bankroll in his casino and paid out all when closed btc dice. Betking owner dean has held 5k btc long time. Poloniex i trust also. Many sites has been trusted longer the polo without they have scammed. I think there is alot more then just site you can trust.
I have invested on just-dice.com for long until now since clams came and site up. I could say i never have a problem and everything is smooth.
Dooglus is the person i trust most in crypto world. I just not like clam anymore