Hopkins didnt loose for 10 years at middleweight and fought everyone that was there to fight. Sturms reign is on its way to 10 years and in that time consists of a KO loss, a gift decision and him outright avoiding major names that passed through the division such at Taylor, Winky, Pavlik, Williams and Sergio.
When there were no names at 160, Hopkins fought guys coming up and then moved up in weight himself to make the big fights with Tarver, Pavlik, Dawson, Winky, Pascal and Calzaghe.
You really have to go out on a limb to even compare them which is why you want to throw out the Trinidad middleweight win even though it was a middleweight defense after trinidad KOed a full size middleweight his last fight. Theres no reason to believe trinidad couldnt KO some of those guys with less than 20 fights that Sturm has been fighting.