I know three people who do vote counting every year. They all agree that the voting went very smoothly, with less crowding than usual, and the counting took a third of the time it usually does. This is unrelated to the security issues, but to them, the benefit was very clear

I don't get it. How are we unable to make a reliable mechanism to increment numbers and then print the result at the end?!

A known bug is that the counting machines doesn't validate the number of votes per ballot, so you can cast multiple votes by rewriting the RFID chip with a NFC enabled phone.

And even if they address that particular bug, because of the inherent nature of the political process, parties' representatives will always want to count the ballots by hand to prevent fraud.

EDIT: As of this moment there is no way an argentine political party would accept black-boxing an election.