It would only be an upgrade if Vargas was never needed, or replaced with someone equal. Considering most teams have 20-30 starts with a 6-6.50 ERA, they need SP depth. They have some of that now with Parra, but if you're looking to have Manny replace Claudio, who gets those starts when injurues or ineffectiveness occurs? Other than Zach Jackson, the AAA cupboard is mostly not ML ready, and Zach isn't likely to do any better than 5.50, at least not right away.