[Okay, something needs to be understood. While on a ship to ship basis the Argentinan BC would probably win, there's a big difference between the Argentinan navy and the Brazilian.
Argentina: Lost a fair few ships and has to make do with more for less. Thus, the Argie BC uses old guns but makes up for it with heavier armour.
Brazil: Has existing logistics for the weapons specified in the ship. If the Marinha Imperial could have afforded to go hog wild, I guarantee you if I'd given Swamphen free reign he'd have come back with something even the Euro powers would have had bad dreams about. However, it can't afford that kind of spending with a general modernization going on, so it has to make do with the ability to produce more BCs than Argentina.
However, you all are probably right about the limitations of this ship and production will more than likely stop at four.]