There's a lot to factor in. Both at their primes:
- Lewis was still about 20-25-lbs heavier and knew how to use his weight (it had him getting winded and take a middle round off here or there)
- Tyson was in top condition and had better balance and stamina.
- Tyson moved his head not his just hands; he was hard to hit and when he was hit, he took it well.
- Lewis had already learned his lesson about throwing with guys and was cautious which kept him from getting careless, so he could cut you up as long as he was able to lead at a slow and steady pace.
- Tyson's mind was still in boxing at that point (before the women, drugs, and the leeches got to him)
- Lewis had Steward which negates the Ko loss to Mcall (who was trained by Steward) but not the KO loss to Rachman (Poor training?)
- Tyson had Rooney, Jacobs and other support to keep his head straight.Tyson had less reason to be afraid--he was always mentally insecure but in the right settings (trainer, polished skills, no distractions) he was a machine.
- Is the ref going to allow Lewis to clinch/ hold/lean like he did with Evander to sap away his opponents legs?
- Will the ref allow intimidation tactics from tyson (no arm bars in his prime but definitely forearms).
- Height/Reach would have been an advantage for Lewis; Tyson was no sitting duck like Tua (Who was also 30-35lbs over his prime weight)

There's a lot of stuff to be taken to into account. The more I take into account, the more I lean towards tyson. No annihilation or obliteration. Lewis was good at playing chess when he was given time and space. He knew to pick apart the brawlers and bum rush the guys with the jitters. It just seems that with the prime stipulation, Tyson's stock seems to rise more than Lewis'. Most people don't remember tyson being a student of the game and boxing because all they remember are the one punch knockouts and scared opponents taking a beating, then folding. Make no mistake, many of those guys knew they stood to gain more by beating tyson than losing to them. Don't think they didn't train, try or plot to. Tyson in his prime needed a less specific set of circumstances in order to be successful. He went about his work the same way no matter what the opponent brought. Tyson would have less issues about fighting a Prime Lewis with a height and weight advantage than Lewis would have trying to negate the pressure from a Prime Tyson. Just My opinion.