Well, I don't think anyone thinks Castro is going to be a 30+ HR guy like those two. As to your question, hitting 31 doubles in 500 PA's in the big leagues at age 20, along with his swing and body type are pretty good indicators that he's going to hit more HR as he develops. I think you and I are on the same page, but I seem to get the impression (maybe falsely) that people DO think he's going to consistently hit 30 hrs a year.