The problem is that most students who look for SAT classes end up with inexperienced tutors, high school teachers dabbling in subjects they do not really understand, or the worst of all solutions: the generic
PR, Kaplan, or Sylvan classes. Most invariably, the generic classes are taught by students who have received a training that is almost comparable to the class they are teaching. Further, they are teaching from a manual that, to the best of the combined knowledge of this forum, does not contain more than the material from their $20-30 publications. Companies that DO not use the official test published by ETS/TCB are simply to be avoided at all cost. Why endure the combination of sub-par "teachers", error-filled material, and misleading tests?
On the other hand, there are tutoring companies that take great pride in offering a superb package. Those companies tend to be privately owned and use very few hired tutors, if any. Any respectable company won't have a problem in providing an extensive list of clients, as well as a DETAILED plan of study. Make sure you call the reference!