As I hinted at earlier. Let's wait to see if Beterbiev unifys at LHW and possibly move up to CW and attempt to do the same there. I think he can and will if politics and age don't prevent him from doing so. If he does that absolutely merits a serious discussion as to how he fares against the likes of Marciano and Charles.
He's always gonna have that "what if?" factor for me, just like Mike Tyson. I uundoubtedly know he could have been a great if he had gone pro early on, but I think he came to the pro side too late. As it stands, I couldn't even hesitate to pick Bob Foster over him, let alone Charles.