I just finished the PR course and managed to crack 700. I think that it is an excellent course with excellent resources. But - like all courses - depends on the teacher.
I think that the best thing to do is to go to the first session and see what teacher you will have. If not satisfied byt this first impression - ask to switch to another class. PR is very accommodating to your requests, and guarantee your satisfaction.
Hope this helped. Good luck on the GMAT.