Check this post out that I made compiling a bunch of old sparring stories on many great heavyweights:
https://www.boxingscene.com/forums/showthread.php?t=693093
I remember Emanuel steward saying wlad had more 1 punch power. But then he said Lewis was more versatile. He said wlad could ko anyone at anytime with 1 punch because of his power. Lewis put more punches together. Idk it was a long time ago.