Reggie Johnson IMO is one of the most underrated fighters of the 90's. He was an excellent middleweight who had very good skills, and speed, and pretty good pop as well. But could he beat a prime Nunn?
No, IMO. Johnson was a good, decent middleweight contender but not a spectacular one. He was the kind of contender who could usually give a good account of himself in big fights, but (except for his fight with Steve Collins) he usually did just enough to fall short. If Sumbu Kalambay (a much better and more accomplished boxer than Johnson) couldn't box against Nunn, Johnson wouldn't have been able to either. And if he couldn't outbox Nunn, he couldn't beat him. IMO, it's a bad style matchup for Johnson, if nothing else. I say Nunn beats him easily and decisively.
Well I agree that Nunn wins, but calling Johnson just "decent" is an understatement IMO. If a prime Johnson was around at 160 today, I'd pick him over every middleweight except for Pavlik. I think he'd have schooled Taylor. But having said that, I agree with you that he's not outboxing Nunn. Micheal was just more gifted, quicker, and rangier. Other than Toney, Jones, and maybe Hopkins, theres no middleweight since Hagler who I'd pick over a prime Nunn.
Don't forget, Johnson actually blew TWO title fights with Jorge Castro, who was a tough but otherwise pretty limited and un-talented (and OUT-BOXABLE) fighter. Given that, I wouldn't be so quick to make Johnson such a clear favorite over guys like Taylor, Miranda, or Abraham. Johnson might've been more talented/skilled than them, but IMO he was a wee bit of a choker.