It's a little scary that people are now referring to Castro in this fashion, as some sort of established known quantity too good to be a fair comparison for any other prospect. What is scary about it? Castro went from a decent/good prospect in the Cub's system to a top 25 prospect in all of baseball. Even if Castro never pans out in the major league level, according to all reports his trade value is extraordinary at the moment. Hopefully, the Cub's system can effectively judge which prospects they should sell high, and which ones are worth holding on to. Normally that sort of language is used with some discretion, "nobody is trying to find the next ARod here, but Castro is a legit prospect". Nobody is trying to find the next Pujols here, etc. We absolutely should be trying to find the next Castro. He was a talented player who became a really good prospect, but that is all he is at the moment, a prospect. He's still got a lot to prove before he achieves "okay let's not get crazy here and compare guys to Castro" status.