I always try to find a fighter that I can match up with Pep. of course Pep is a faster, more experience, better defensive fighter. However, I think the Ruben is a complete and slick boxer, that when it's go time, starts unloading until the fight is over. Wille would be dealing with Saddler esqe power. I think that Pep wants to do his usual routine and Ruben will let him. Ruben will concede to track Pep. Rubin is not a grab and brawl guy. He is more like a set traps and try to get you to engage in prolonged trading. Pep will not engage, he will look to keep moving but, sooner or later he will have to deal with Ruben power. I think that because Ruben is adept at slipping and countering with his power, I feel he can stop Pep. I don't consider Pep the strongest, toughest guy around that he can withstand the type of leather the Ruben can produce and I think that Ruben can stay close and land enough shots to hurt Pep and with that power stop him late.
The featherweight Olivares did still carry power, before he ko'd Ruben Alex said he thought he was going to go down several times from his punches. Though Ruben could box very well when he had a mind too anything he could do was less then Willy so its the attacking Olivares that would have the best chance. Willy's skills here just a level above even the best Rock-abye-Ruben.
I'm just about the biggest Olivares booster on this forum and I do see any way Olivares wins except for an opportune punch.