The NAFC is a relatively new organization, but they have been around for a while. As a trainer/club manager who is certified through ACE, ACSM, and a CEC provider for the NAFC, I can share my experience with you.
When I initially looked into becoming a CEC provider, I was skeptical as I had never heard of this organization before. What I have found, though, is that this organization is all about focusing on injury prevention, as Personal Training has received (as I am sure you are aware) such a bad rep for “hurting people.” They want their fitness professionals to come out with a working knowledge of what they are doing. As far as their exam process, SIX tests are required to pass, with a passing score of 80% or higher. Most organizations only require one exam and a 70% passing score. NAFC wants to know that they are putting quality trainers out that will uphold the standards and integrity of working with the livelihood (and physical bodies) of their clients.
That is not to say that NAFC is better than any other organization, or that they are claiming to be. They just have a very different focus. I love my certs equally, and have benefitted from all three of them. Each has their own valuable education to offer. So, it really depends on what your focus is. If you know you are going to primarily be working with athletes, NSCA is the cert you will want to look into.
What I really like about this organization is that they stop to ask the question WHY. Why are you doing the exercise? What is the purpose? With all the various methods of training these days (p90x, Crossfit, etc…), how will the exercise you are asking your client to perform functionally benefit that person? Why is grandma Betty squatting 300 lbs? Not only that, if there is a sound reason for her squatting with this much weight, a) can she actually perform a proper squat, and b) if she cannot, then why in the world are you loading her with any weight at all? What is the purpose behind the exercise?
Everyone is correct in saying do your research and contact any specific gym that you would like to work with, as some are contracted with certain organizations and have a preference. Adriadne is correct in that the NBFE accreditation organization standards are very high. They are quite strict, and AFAA is also backed by the NBFE. I can tell you that NCCA accreditation should arrive by early Fall, as NAFC is in the final stages of application. This will likely build more awareness and credibility for larger club and gym chains.
To speak to Karin’s groupon concern, this was solely to build awareness, in being relatively new to the industry (though NAFC has been around for over 20 years, as Karin stated). The groupon will not be likely offered again. I hope this has helped in some small way, and good luck on your path!