I don't like it. It seems excessive to me. Yes he's young and has talent but that is still a lot of money for a defender. OK, he's played in a World Cup Final but by all accounts Argentina aren't exactly inundated with quality defenders.
Still, he's got to be an improvement on the current shower of troute we have at the back. To be honest, just the one new centre half is not gonna be enough to challenge for the top four.