Colvin and Vitters are probably the most questionable players on that list, though Colvin's major league career to this point (including last year and the start this year) makes him look like a ML player of some degree - I tend to think he's more of a 4th OF type who won't walk enough to merit a starting role, but the organization thinks more highly of him. Vitters hasn't had a huge amount of success in the minors, but as has been mentioned, is very, very young for being in AA. At some point he's going to have to produce at a high level, but he has an impressive skillset (including a lightning fast bat) that could translate well. Cashner has shown the ability to utterly dominate throughout the minors. He struggled in a bullpen role last year, but I'd argue he should have still been starting in AAA at that point. Durability is a major concern and probably the only one with him - if he can stay healthy and strengthen his arm, he'll be a top of the rotation starter. Jackson has also been dominating the minors and is still young for his league. He may never become a superstar, but it's really hard to argue he won't become a legitimate starting OF - perhaps even a strong hitting CF - within the next 1-2 years. Simpson hasn't been a pro for a full season and, so far, has dealt with mono and another significant sickness. He's currently pitching well underweight and his velocity is still down. It's simply far too early to say anything either way about Hayden. As for delusions of grandeur, the minor league system hasn't been as good as it should be at this point overall, but has seen significant improvement since Wilken took over. There's a lot of promise throughout the minors, but it's way too short on legit superstar type players (McNutt might qualify, maybe Jackson or Vitters if they really take off).