Our class chose the Northwestern Review and although I cannot speak for everyone, the general opinion was a 'thumbs down'. My personal complaint related to the way I study (structured, with a few important mneumonics), the review books were organized in a strange, distracting way with mneumonics for >75% of the information. There were also loads of mistakes.
On the other hand, the class ahead of us chose Kaplan and most of them did not like this course either. I think these review courses are a bit of a catch-22...the longer you sit in lecture, the less time you have to integrate the info for yourself. However, if I had to choose again, I would go with Kaplan. Hope this helps!