Pros
Next Step differentiates itself from your run of the mill prep companies by not hiring inexperienced tutors who will only deliver a scripted course to students who have, by and large, already been there and done that. To get a job with Next Step you have to have multiple years of prior tutoring experience which you can back up with references and pass an evaluation with an academic manager. If you have a high score and years of experience with Kaplan or Princeton Review but find yourself not given an appropriate number of hours or pay commensurate with your abilities, this is a good opportunity. It lets you exercise your craft and use your best judgment as a qualified tutor.
Cons
It's a smaller company, so if you only want to work locally, your student load will probably be sporadic. The way around this is to cross-train for other tests or offer to teach the course via video-conference, which is a big part of Next Step's business.