I've played with Berklee-trained musicians. It's a mixed bag. They won't turn you into a great musician against your will. This is true of any education. And you have to already be **** good when you apply in order to make full use of the opportunities that they offer.
Oddly enough Berklee is considered to be a jazz school, but the players from there who I consider to be real stand-outs (performing at an international level, or well on their way to doing so) have chosen to earn their livings outside of mainstream jazz.
Mainstream jazz really doesn't make money. Also, Berklee is also really strong in the broader field of "Commercial Music" which includes things like film scoring and pop-oriented genres.
Oddly enough Berklee is considered to be a jazz school, but the players from there who I consider to be real stand-outs (performing at an international level, or well on their way to doing so) have chosen to earn their livings outside of mainstream jazz.