This is a long-running debate and I'm not sure that there is an easy answer. There are always two sides to the story. For instance, some important research may not have 'seen the light of day' had it not been for this suite of journals. On the other hand, the more successful a journal is - potentially the more elitist, inward-gazing and nepotistic it becomes. The same debates rage in similar institutions in my clinical field i.e. The BMJ, the Lancet, the Cochrane Library etc in that they are selective and distort the overall real picture of clinical research through 'screening'.