I did my PhD through GST and it took me about four years, although I had been working on the research area for a few years before that. I did it on a quasi-full time basis. This means that although I was working, my work allowed me to do much study. What I found most helpful was the support that I received from GST and North West University. GST is excellent in that they reply to emails very quickly, they guide you through every step of the way and they are always ready and willing to step in when you are in difficulty. I also found the North West library staff very helpful in helping me to trace and obtain obscure material. They too were only too willing to offer their services whenever I needed it. My supervisors were excellent too – quick to reply to emails, thorough in making corrections and suggestions, always learned and up-to-date in their area of specialisation.
From my experience, I would heartily recommend GST. They are authorised, well-known and established and genuinely interested in helping their students to improve and flourish.