Look man, Ali was an inch taller than Holyfield and an inch shorter than Sanders. But he had neither the chin of Holyfield or the punch of Sanders (or the chin either).

Ali was at premium 212lbs. Anything you try to rate Ali above that rate much is a blown up version (i.e. he was fat and unathletic). Holyfield by comparison was in FACT 215-220lbs of solid muscle not a scrap of fart and supremely conditioned.

Incredible, you are trying to pass off one of the laziest trained boxers at those weights you extrapolate for him, even his own trainer made statements about the slovenliness of Ali, as the same size as Holyfield or natural HW's!

Now I know Holyfield is artificially pumped up to that weight. Were we discussing ethics here, sure I would agree with you, Holy should be a cruiser. But by todays standards, so should Ali!

You are wrong, Toney stopped Holyfield, Bowe knocked Holyfield out, testament to the power of one of the technical giants of the modern era.

And Ali was stopped by Holmes, a much superior boxer than Ali anyway!

Sure it was end of career. And you can say he was never KO'd any other and that makes him the best chin.

So I suppose by that logic then Floyd Mayweather has the hardest chin of all time too then right? Cause he was never KO'd.

Or for HW's I guess Marciano would also survive modern HW because he was never even beaten let alone KO'd?

You would like that!

But wait, then you also have to admit Vitali Klitschko and Nikolay Valuev to that magical un-KOable list too then because neither were they!

You see where we're headed? Obviously the POWER of punches across the era in question is a very important factor in remaining un-KOed.