All top quality for me but I am biased because my friends and I back in the day were in a gym with John the Beast Mugabi so it’s him for me.
I am in the same boat. Flash and i had a great discussion representing both ends of the spectrum per Mugabi a while back. In the early days here he wasn't overly rated at all.
You could easily have Mugabi ahead but it's not as cut and dried as a knee jerk reaction would imply......IMO
Boza Edwards beat Schoolboy. That's all there is to it. The best single win out of all of them, over somebody who was already recognized as an ATG at the time, and would do it again. No contest, really.
Boza Kalule Mugabi Ouma Boza beat teak tough Bazooka Limon and Bobby Chacon. Gave a peak Arguello a decent fight and moved up to lightweight and beat various contenders. Kalule was a solid World champion and gave Leonard a decent fight before losing. Career took a downwards slope after that but did floor and outpoint the excellent Sumbo Kalambay (in his hometown on points) and gave a peak Herol Graham one of his toughest nights. It must be noted that after losing to Kalule, Kalambay beat over the course of his next 7 fights the undefeated Herol Graham and Mike McCallum (coming of kos of Don Curry and Milton McCrory), Iran Barkley (who then knocked out Hearns) so Kalule´s victory looks great on paper. Mugabi looked good up to Hagler and then fell to pieces unfortunately after that. Real shame as he a lot of potential. Must admit to never seeing Ouma in action. Heard about the whole boy soldier part of his life so glad he managed to escape from that hell. Has some good solid wins (always liked Vernon Phillips) but nobody of real note.
I’ll go with Boza but it’s very close with him over Kalule. Ayub had a fine career and is probably a bit under-appreciated but Boza mixed well with the very best in his weight and time so tip of the cap to a great warrior.