people have been quoting an average of 1000 radium gets about 1 block per day (1radium coin + fees)
it wil take 6 hours from when the coins hit your wallet or after they perform a stake to mature.
rewards estimates are... estimates, it could take a week to get 1 reward or 10 seconds after they mature.

seriously its like any other POS coin. interest this year is 20%, so if you have 1000 coins expect to run your client 24 hours a day 7 days a week for 265 days and on March 6th 2017 you would expect to have 1200 radium. at that rate 1000 coins is more like 1 radium every day and a half.