And specifically what you have seen from Haye in these fights to indicate he will win against Wladamir.
Confidence mostly I think. Hell Ruiz was champ for quite a while and beating a former champ is definitely an accomplishment. BTW, Klitschko by KO7 over Haye
Ruiz was a fraud and a joke as a "champion" (really, he was a beltholder, nothing more, and a fraudulent one at that). Without Don King's influence to get him rankings he didn't deserve, and a free pass from refs for his illegal holding, Ruiz would have been lucky to win a regional HW belt.
They were good preparation in the sense that stupid British fans gave him a bunch of money before he gets sparked by Wlad. I would have done the same thing.