This thread has been done quite a few times but I say Ramirez probably cause he is the harder puncher of the two.
My vote goes to Castillo. Admittedly, I'm a little more familiar with Castillo than Ramirez, but good fight for sure. I mainly thought Castillo was more accurate and ate up the style of fighter that Ramirez is. He knew exactly when to throw inside hooks and uppercuts and didn't waste very many punches despite being so active. Both had granite chins, so I'd see Castillo taking a 116-112 or a 115-113 type decision.
Two very strong guys indeed, Both come forward, Both with Great Chins, But Castillo has that little extra versatility, Ramirez was a Lightweight version of "Gort" Chugging Forward, Very stright Line, It worked against the good "ön Top'" fighter Edwin Rosario and a Shell of Boza Edwards, But someone without those frailties, and a bit of verity, should be able to Map Ramirez and use his only forward gear against him, Ramirez brings toughness and determination but no unpredictability, Castillo does, when compared to Ramirez, has a few more cards to play. Castillo on points in a tough encounter,
Ramirez by late TKO around the 11th or maybe even the 12th, while behind on points. While Castillo was the more skilled fighter of the two, Ramirez was the harder puncher, and was much more durable and had a stronger chin.
He probably deserved the decision against Arguello too. Castillo does not have the versatility to just 'outbox' Ramirez. He'll be drawn into a scrap and Ramirez tends to win those.