Your only taking into consideration chins, not age or stamina or heart or anything else. Oliver McCall has a chin of steel, but the guy would take too many punches from somebody like Wlad and get stopped. Toney would too. The only guy I could confidently say is Hopkins. Nobody in his current division or below stops him. Chin is too good, defense is too good, plus his conditioning is still great.
It would more surprise me to see Hopkins get stopped than the others. Mayweather if he's active. I wouldn't put faith really in anyone else. Vitali could get injured during a fight, etc., so it wouldn't "surprise" me.
Mayweather..the mans touched the canvas 1 time because he put his glove to the ground after he messed his hand up against Chavez
Are we talking fighters that can't get stoppage or won't get clean KO'd? Because if it's the latter I could name tonnes.
His chin honestly is pretty unproven .... the guy has rarely ever been hit flush , his defense is amazing, chin? We don't know, because of his defense ... kind of the same goes for hopkins..
Toney and Hopkins because they have proved it over time and moving up in weight against solid opposition.
JC can definitely be KO'd , he has been downed in his last two fights against 43 year old Hopkins and the Shell of Roy Jones jr... If he gets in there with a younger guy who has a lot of pop... I can see him get KO'd .... prolly won't happen though.