Possibly, slightly. If only because Wilder was a bigger, more dangerous opponent. Povetkin was dangerous too, but Wlad wrestled him and that taints the win a bit. Byrd, a smart boxer, but I was never a fan of his light-hitting style, so it's hard to say.
Povetkin, Byrd 1, Chagaev, Peter 1, Byrd 2, Thompson 1, Schultz, Haye, Brock, Ibragimov, Peter 2, Chambers, Brewster 2, Thompson 2, Castillo, Botha, Mercer... Something like that
His "win" over Povetkin is an enormous skidmark on his record, hardly a triumph. His marquee win is probably David Haye. The truth is he beat a bunch of low class, short, old or blown up opposition. Vitali, the same. The difference is that Vitali didn't get sparked out by mediocre opponents in the process, down in other bouts and outclassed over 12 rounds, also. The boxing hipsters, who moaned about how boring he was at the time and how bad the era was, will no doubt pipe up with their contrarian and farfetched answers in an attempt to push their biases regarding nostalgia and their prejudices regarding the top dogs of this era.
I think Povetkin is his #1 win. If Wlad and Vits had not been around he's have been #1 no question in my mind.
What's so special about his Haye win, besides the (mostly Bri'ish) hype surrounding it? Haye didn't do much at HW at all. A stinker against Valuev for a paper as they come belt, and the firefight with Chisora are his highlights. A lot of total pushovers like old Fraudley, old Huggy Bear, De Mori, Garbage etc... I believe he would have lost to most of Wlad's better opponents.
I think his showcase fight was Haye, for Vitali it was adamek (highlander) somebody called wlad the "non killer" because of fight s like mccline or Corrie Sanders. They said Vitali was as animal. I think they were both wrong, wlad spits out plenty of venom and Vitali was embellishing the Lennox fight as soon "as he knew the fight was stopped," Vitali in the second Phase of his career bested arreolla a brilliant breakdown display of a rugged brawler.
He beat a prime undefeated povetkin who was looked at as one of his most dangerous opponents of his career at the time. It was a great win.