As near as I can tell, having worked in a medical school for two years now (leaving next Thursday for med school!), academic medicine can offer many pluses and minuses.
My experience has been with pulmonary and critical care docs who have gone into academic medicine via a fellowship which entails laboratory research. Once this is accomplished, the board certifications for pulmonary and critical care medicine are acheived, and the physician is eligible to become a primary investigator or an attending at a teaching hospital who oversees fellows, residents and med students.
Pluses include being able to go, as I often heard quipped, "from the bedside to the bench and back to the bedside," doing research which can help flesh out the mechanics of disease and physiology in the lab and gaining a better feel for management of patient care. Also, contributing to the welfare of newcomers to the field (if you're a responsible academic physician)can be very rewarding.
A big minus is that, unless one gains very large grants and can therefore jockey for a sweeter deal from the school one is affiliated with, salaries are far from competitive with those of private practitioners. I have heard many a disgruntled doc proclaim he "should just go into private practice." While this is always uttered in lower moments (balanced by the rewarding moments), it is a real consideration to make: can you cope with having gone through the training process of seven to ten years only to secure a modest salary? If the answer is yes, then that hurdle will not impede your progress, but if the answer is no, then serious considerations should be given to private practice.
Another drawback, as with any laboratory investigation track, is the potential for failure to acheive. In an academic setting, often the p.i. who is a physician will go "on service" (be an attending or consultant) for a month or two each year. Research can suffer (especially in the case of a budding p.i. who has a modest lab to begin with) from these extended absences.
I've had several years of laboratory work and I personally feel that I would rather be in private practice. I might change my mind later on down the line, but right now I cannot see myself making the time commitment to maintain a practice AND a laboratory in addition to my plans for a family.
Hope my comments are helpful. Also, I acknowledge that there are, as above listed, many types of academic physicians out there. My comments are limited to my own experience.