Even though this was some time ago, I will give an answer as no one else has.
I have taught the materials, reviewed the materials, and taken the certification exams of several of the different certifying organizations. NCSF is one of these. I didn’t find their study materials to be any different from the other better known organizations, no better and no worse. I didn’t find their exam to be all that different either, no better and no worse.
There are a few things that I didn’t like about their system and these may have changed, but I am not sure. One was that they require their certified professionals to take some of their CEC courses in order to recertify. I didn’t find their CEC courses to be interesting. And their certification is not well known or given as much credence as many others.
I reviewed their materials and took their exam to see if I would want to include their material in my Personal Trainer course presentations for people wanting help preparing for a certification exam. At this time I do not. I have not had any requests to teach their material for certification.