It is compounded interest – so assuming the apy does not change you actually need to stake for a year to get that kind of interest. It is not a scam since there is backing for the tokens – at least 1 dollar per TIME so you have to weigh the insane apy against the possibility of the coin going down quite a bit. Looking at marketcap growth is useful in this respect. Personally I find it fascinating and I think these reserve coins have big potential but it is just as others already said: very experimental