Agger hasn't been anywhere near as good as he was in Benitez years.
Coates is a very very very good CB, i put him in my fantasy team the second liverpool signed him. However we'll see how he does in the Premier League, as it can take foreign players 1 or 2 season to adapt. Even after a good start in his first season Coloccini was found wanting occasionally due to the pace and physicality. He had 5 or 6 bad games in his 1st season out of 38 and that was enough for Match of the Day pundits to have a go at him and scapegoat him, and thus making the masses who hardly watch Newcastle play 90mins think he's a bad defender. That is probably still the reason some ignroant posters today think he sucks.