Depends who is throwing the leather. Charles is one of the best P4P fighters of all-time. He was smart, he was accurate, he was fast, he was strong, he had decent power (at HW), he was durable, and he had great stamina. He also had experience in beating other highly talented fighters like Burley x2, Moore x3, Bivins 4 out of 5, Marshall 2 out of 3, Maxim x5, Walcott 2 out of 4 (should have been 3 in my opinion), Louis, and others. He fought a prime Marciano in his 98th and 99th pro fights and gave him hell. He was well past prime and went just 10-13 after the Marciano fights. In his 94th and 95th pro fights he lost close and questionable decisions to Harold Johnson and Nino Valdes... Charles was clearly a better fighter than either one of those men. Johnson made a lot of fighters look foolish. He wouldn't make a fighter like Ezzard Charles look foolish. Charles isn't coming at a fighter like Jack Johnson without a very good fight plan. I think it would be a great fight. Johnson had wins and losses vs. some great fighters and some not so great fighters like Klondike Haynes (LKOby5, but he also beat Haynes), Joe Choynski (LKOby3), Hank Griffin (he also drew with Griffin), Marvin Hart (L20), and others. He did beat very young versions of Sam McVea and Joe Jeannette (he also lost a DQ to Jeannette). He beat Young Peter Jackson and Sam Langford. He dominated little white HWs like Bob Fitzsimmons and Tommy Burns. He outboxed Philly Jack O'Brien in the eyes of most. He knocked the crap out of the tiny Stanley Ketchel after Ketchel dropped him. He stopped an old Jim Jeffries. As good as Langford was, not much can be taken from Johnson's win over him in my opinion. Langford wasn't exactly at his peak when he fought Johnson... he had been recently stopped by Jeannette (8th round KO and Young Peter Jackson stopped him (KO5) in his fight after Johnson. Dave Holly and Larry Temple had clearly outboxed Langford as well (that's what was reported anyway).