I am in the middle of reading that book and love it. My girlfriend just finished and she loved it too despite finding surgery in general a little off-putting. From the book, it seems clear that like any super specialty the pay is good but there are many many other specialties if that is the primary consideration. It is also clear from the book that it is in many ways a field of a few superstars and a number of good surgeons who just aren't good enough to suceed at congenital surgery. The author discusses the correlation between case volume and competency and makes a rather convincing argument that what would be in the best interests of the kids needing this type of surgery are larger specialty centers focused primarly on this type of surgery rather than peds cardio surgeons shoved into other programs. In this way, the surgeons performing these surgeries are adept at them rather than seeing a congenital now and again while performing adult cardiac surgery the rest of the time. I don't know if this would ever be put into practice, but if so it would seem to really limit the number of peds cardio surgeons needed in the future. For training, I believe that the current "power" centers are Boston Children's, Michigan, Cleveland Clinic. Really just read the book. it's awesome