Are all Heavy armors equal?

1) Are all heavy armors equal despite them all saying 40%?

2) If Novikov is 40% defense too, but a 5 piece Morozov is 40% but 10% undersuit, how does the math work here?

3) there's some rumors going around that the Overlord armor set is buffed higher than displayed in game. Just rumors so far, nothing tangible. Anyone hear this about the new armor sets?