Mythologycally he matches up to every hw win or lose, that's how much potential he has in all time greats. I agree with that post from cj: that Ike versus Lennox would have been a treat to us boxing fans!
Vitali was beating the brakes of Lewis before his vision went to hell. I think Wlad would beat him too, if he fought a technical fight and kept Lewis honest. Holmes could give Lewis fits too, although Lewis' extra size would probably pull him through.
Imagine that Rahman had declined to rematch Lewis and I made the argument that he'd always starch Lewis with a big punch. Actually, that's more likely than Vitali's face falling off every time he fought Lennox.
Prime Mike Tyson beats any version of Lewis. Holmes and Holyfield would have a good chance and Bowe vs Lewis would be a 50/50 matchup.