[dangero]

Bitshares did low cost transactions at high volume years ago, so I'm never quite sure why Nano gets so much attention because those features aren't novel.

Furthermore, free transactions with minimal POW don't create proper incentives and will not scale because there is an extremely low cost to spam the network. This means you can essentially use full historical nodes as a data storage for anything you want.

[stri8ed]

Adding to this, representative nodes (DPOS) do not get any rewards for being online and behaving correctly. Which is a recipe for tragedy of the commons. Worse yet, a voter can issue two conflicting votes, and the system has no mechanism let alone penalty for handling this. The defense against these attacks seems to be, reps have stake, therefor they wont take actions detrimental to coin value..

The marketing is strictly speaking false. A transaction is not instant, as you must wait for sufficient time to ensure that a conflicting transaction has not been published (and hope that you are not network partitioned). Otherwise, you might as well settle for "instant" BTC 0-conf transactions. Free, is debatable, considering the difficulty of POW that would be required to effectively deter spam.