How would Prime Joe Calzaghe fair at super middle and light heavyweight today?

[RubenSonny]

I'd favor Calzaghe over everyone but Ward.

[Check]

Beats them all on the same night. Calzaghe is vastly under-rated

Pretty sure it's the other way. His undefeated record has made him vastly over-rated. Calzaghe would do well because he is a solid fighter but he certainly would not beat all of the best SMW and LHWs. Those two divisions are better than the guys he fought in his career.