Froch. He's naturally bigger and his power backs people up and makes them afraid to throw. Point in fact: Abraham walked through Miranda. He did not walk through Froch and he certainly wasn't 'slipping' any punches either.
Definitely Miranda. Miranda probably hits harder than anyone at Sm along with Abraham and maybe Andrade.
In their first fight Miranda broke Abraham's jaw, remember? Miranda has power only in his straight right hand; but Froch's accumulating punches have a much stronger effect.
I think Miranda punches harder. However, I don't think Froch is the naturally bigger of the 200. I think I read or heard on a telecast that Miranda walks around at 200. I know against Bute he blew up to like 186 on fight night.