Mayweather is a level above Calzaghe , he has gone through the weights , fought much better opposition.
I liked the comment - " They maintain that he got to Hopkins and Roy Jones when they were past their primes " that is priceless , RJJ had twice been KOED , and Calzaghe slapped him for 12 rounds and got floored by Hopkins and Jones.

Ebony and Ivory - chalk and Cheese - which ever way you look at it , Calzaghe aint no Floyd Mayweather in achievement . A British great in some peoples eyes , that's the bottom line.