how does an investment on this site works? or any other gambling site, but specially this one. what i mean is if a make an investment for how long will i be receiving coins, what is the average time for ROI, anyone with experience in this area??
How much you earn a day completely depends on the number of users and of course whether they are winning or losing. We can't give you an approximation unfortunately. However, you can check out our stats page to see how previous investors have done at
https://www.satoshidice.com/stats/Satoshi Dice uses a 1.9% house edge and backers get 50% of the house wins or losses. The slot game uses a 3.5% edge. This means that the dice game gives a 0.95% Expected Value (EV) that is shared by the backers, and the Slot Game gives a 1.75% EV to the backers.
Of course there is always a risk of investing in the bankroll. As you can see from the stats a page - A player won big on the slots. But as you can also see profit has continued to increase since then.