I like them both, but I voted for Don Michael because although he was ruthless, it was 'business not personal' and was all to try and become legitimate.
But I do think he went a bit far with Fredo frown

"My wife was weeping before she fell asleep, outside my window I saw my Caporegimes coming to the house and it is midnight. So, Consigliori of mine, I think you should tell your Don what everyone knows."