Toney, RJJ, Tyson, PBF, and Ali. All could take shots to the body, and never seemed to be in great discomfort.
Muhammad Ali took body punches better than anyone I've seen. He took some brutal shots to the body in Manila, but still finished strong in the intense heat in fast-paced 14 round fight. He also took some hard body shots in Zaire as well. Strange that Karl Mildenberger seemed to double over Ali to the body but Joe Frazier and George Foreman didn't. James Toney is another guy who was great at absorbing body shots.
Margarito is strong both upstairs and downstairs. Not many guys would get up from a perfect liver shot and go on to win a fight. He's also been hit with solid body shots from Clottey and others and didn't even flinch. He does deflect a lot of it with his elbows though.
Ali could take one helluva good shot to the body. The guy survived those winging smacks from Foreman and went all those rounds with the great Joe Frazier. That guy's ribcage is made of steel. Of the guys right now I'd toss in there is Zab Judah as another guy having a good sturdy body. The guy took much punishment from Miguel Cotto and I never even saw him wince. He also was able to stand up to a body shot from maybe the greatest body puncher ever, Micky Ward. He doubled over from a mean left to the body he took, but unlike so many Micky faced, he actually kept himself from going down and recovered enough to win the fight..
Good points lol. Also I might say after pacquiao got blasted to the body earlier in his career, I am pretty sure he has vowed to never go down like that ever again lol. Pacquiao can take shots to the body I'd say. I've seen him take some and he walks through them.