well, imo, holyfield was physically bigger and stronger then spinks anyway so spinks wouldnt fare as well as holyfield competition. the most winnable fight would be foreman. spinks had enough speed and skill to win a decison.
I don't see Spinks beating any of the fighters mentioned above. He beat Holmes albeit a tentative Holmes and an older Larry, then went on to beat a washed up substance abused Cooney and Stephan Tangstad (Huh?) before being annihilated in 1 round by Mike Tyson. Spinks was one of the greatest LHW's of all time. Of that there is no question. But up against the likes of Lewis, Bowe, Tyson and even a comebacking Foreman he is simply out of his league...by a mile I might add. Holyfield was a lot more physical and quite a bit stronger than Spinks and had the chin to cope with a true HW's punch whereas Spinks didn't and Michael knew this. Look at the look on his face when he entered the ring against Tyson. He knew he had no chance. He was meeting a true primed HW this time. No more soft touches. Spinks' brief foray into the HW division was mildly impressive but carefully arranged as well....until he chose to fight Tyson that is.