I think Vitali is the best heavyweight by far and would be one of the best in any era. Vitali has never even been knocked down or seriously buzzed so a fighter would have to somehow outbox him. Vitali's 2 losses were due to shoulder injury and a very bad cut. But Wladimir would have his troubles in certain eras with certain guys because of his not so durable chin. Wlad has been KOed by 3 much lesser opponents and almost a 4th(Samuel Peter). Imagine if he was actually in an era of good heavyweight fighters. Due to that he now fights tentative. Wlad has the ability to be a great fighter in all eras but his chin would probably fail him against guys such as Shavers, Tua, Tyson, Foreman, Ibeabuchi and probably a guy or two who are lesser opponents but throw everything into their punches.