My problem with this and BTC is that it isn't even a truly fixed currency supply - as people lose wallets, the bitcoins they contained are permanantly lost beca

My problem with this and BTC is that it isn't even a truly fixed currency supply - as people lose wallets, the bitcoins they contained are permanantly lost because only those wallets (that are now destroyed) are lost. So either you brute force the signing key and try to imitate the wallets or you will never get those coins back. So it isn't just that BTC will (in a hundred odd years) stop growing the money supply, it will probably (sooner than that) start leaking bitcoins from lost wallets, and as the money supply drops deflation grows faster than with a fixed money base.