Id say it was Vitali Klitschko. Even though(Lewis) was getting beat up and out punched the reason being is that he fought a young Vitali, who now dominates the division since the retirement of Lewis.
By a million miles. Everything Vitaly does helps LL. And that is although it because fairly obvious that Vitaly was the best of the two on the day.. but LL was older and may not be prime so prime for prime this places then exactly square... so everything Vitaly does we have to imagine LL could probably also have done.
His win over Vitali and non fight with Bowe are the two biggest acheivements, but those only slightly overshadow his impressive performances against stale Tyson, oldy but goody Holyfield, and prime hungry Tua. But the way he made Bowe throw his belt in the trash rather than getting into the ring is some classic stuff.:deal
Lewis's best clear victory is the first Holyfield fight. The second fight he did not win it by as wide of margine and was close to a draw. The the Vitali fight is a tainted w. Lewis best victory went down in the record books as a draw. I still consider it his best win.
I like how he handled Tua...that was an impressive fight for me. At that time I viewed Tua as having a kinda Tyson-esque aura around him. Lennox made him look like a beginner.