I used CATS Luton for straightforward Distance Learning. The materials were fine, imo. I did have access to some Jep manuals so when I got confused about something I had the same concept in different words to try. If you're Guided Learning, however, you'll have even better resource in your local instructors.
The three chunks mean that you don't have to remember quite as much for each set of exams, which takes a little bit of the pressure off. If you are studying full time, the brush up weeks in sequence would get your exams done within 6 months or so including study time. I work full time plus two other volunteer commitments, it took me just under a year from properly starting study to completing.
The support from the team at CATS was great, they seem to really care about their students, but that may be a case of you get out what you put in. As mentioned on the other CATS ground thread, the YouTube videos are good. There are comprehensive explanations on the question bank.
They are properly up to speed with the EASA syllabus, as far as I am aware. I did old style throughout last year, but at my last brush-up Stuart spent some time explaining the differences and how it would affect individuals and also the new texts etc.
Hope this helps