Dear Friend,
steem and rdd are both social coins, you are rewarded for the content on which you participate. But steem works better in my opinion and the steemit page is better developed. In addition, steem has better stability in the market. I bought a few thousands of rdd 3 months ago at 60 satoshis each and I'm still waiting to recover the investment (LoL!!!)
Anyway, no one know what will happen with both of them in the future but I am getting more profit with steem than with rdd and, I'm enjoying it!!