Is FlexUSD good for real? Interest rates seem too high...

Sorry for my question, I was going to buy some FlexUSD in order to shift something into stable coin. But the question is if that 30% interest rate isn't too much? Nothing is free and a stablecoin that ensure such interest doesn't look good to me.

Can someone explain better? I really don't care about interest rate, I just need a decentralized stable coin that keep its value. Thank you