I think in general folks in the media overcorrect in having too low a cost for rentals, but the Cubs aren't getting a Top 10 overall prospect hitting well in AA for Contreras, even with a quality player like Robertson thrown in. I also don't think the Cubs are really getting fleeced in that proposal, at least in terms of the general value. Vientos is the type of player(50-100 overall, high potential but clear flaws) who does make for a more reasonable match for a half season of Contreras plus a flyer on Smith's remaining potential, and Robertson bringing a Top 10ish and Top 20 prospect doesn't feel out of place even if I might prefer different specifics. They got PCA for Baez last year. If that's the case I hope they don't trade Willson.