Forrest & Wright are both very good yes but the reason they beat Mosley had more to do with the being good as well as horrible match-ups stylistically and in terms of sheer brawn and physical dimensions. Same would go for Mayweather if he fought them. Both of them are much greater fighters overall (in terms of both legacy and p4p h2h) than either Viper or Winky, but they're just god-awful match-ups. Shane facing either of them in the first place was a bad enough decision to warrant sacking his entire management team; rematching was just capital folly.
I could see him losing once and having a few close decisions go his way. The thing about Floyd is he had a really good chin and he was always ON, so he shouldn't lose to lesser foes. It's not like speculating how Lennox Lewis would do vs Ali's resume when you have to factor in the odd slip up. Also if we use Oscars timeline Floyd would be in his prime for every fight. Much respect to Oscar's resume though.
Hmm, not sure I agree with DLH and Mosley being greater than Winky and Forrest. What are you basing that on? Specially Winky.
Forrest has always been one of the most overrated fighters here. His claim to fame was having Mosley's number.