I'm happy with the information and research given by HairLossRevolution, they give good facts, suggestions, pointers, and in their course they got me changing my daily meal routine -- explaining the great importance of healthy diet to fuel hair regrowth. They have good customer service and they respond to your emails with good answers. When it comes to buying the pdf file course, I realized you could find all the information they give online for free and even on their blog/forum... So looking back, I would probably spend the money on products and do the research for free.