I have done very well investing in BTC casinos. Just-Dice is my favorite, although you do have to convert to clams. Yolodice has been legit and lets you do 10x leverage. I recommend SafeDice for people holding XMR. Checking out BitDice as they are having an ICO soon. Thanks!
I think yolodice is quite good for investment because they also have leverage feature so that you can get maximum out of your bitcoin. Also ICO bitdice is running right now looks quite good to invest. They have already raised more than $5 million within first week of ICO. 