It's still good to remember there's still risk involved in investing in the bankroll of a casino. A whale winning large amounts of money can easily wipe you out if you're leveraged on your investment on a site that has such an option, though you will indeed see slow but steady gains most of the time due to the fact that most games are -EV and house edge is at work on all casinos. I used to invest in Crypto-Games and they produced good gains with how well the site's bankroll was managed, though I'm not sure how they're doing recently and even whether or not the site still allows you to invest into the bankroll.