Apart for the Mint/blackcoin war ...
20% inflation and then after 4 years 5% per year forever is insane.
If you really believe in this coin for the long term and it becomes a worldwide currency it will be a worse plague than fiat.
It won't be 20% inflation, but less than that because that 20% presumes that 100% of the coins will sit quietly and acquire coin age, which is false.
Even at 5%, if this were possible, it is less than the inflation of the money supply. If you think that cryptos and altcoins are worse than fiat, then you have no idea how central banks and the debt-money scam works.
http://www.youtube.com/watch?v=iFDe5kUUyT0