Just my thought here. I used three schools. I originally started the studying with PPSC(now defunct) but their notes were good for the technical exams. I passed all first time after studying part time for 4 months. Couple of hours a day when I could be bothered after work.
Then I did all of the Nav exams using Bristol Distance Learning, which I found effective. Passed all except Law (didn't do any study for it) again and used the two week brush up course. Only problem with the brush up course is the large class sizes and the speed they cover stuff. If someone in the class is slow, it takes up time. Resat the Air law and passed using Bristol Law study booklet.
I then used GTS in Bournemouth last year for IR theory. (basically like doing 7 of the CPL exams again). Oh, and some of the Instructors are ex PPSC.
The class size was small, instructors very very knowledgable and the feedback from the exams second to none. I'm not putting down Bristol GS in any way. They do a great job, but I just felt I should mention that GTS have a great pass rate. The fact that Bristol GS have such a lot of high praise is because they are a big school with lots of students going through, so get much more publicity.
Give GTS a call before making any final decisions. Also Bournemouth is a great place to stay.
PS No I don't work for GTS. Just studied with them and passed all first time.
Hope this helps in the decision making process.
PM me if you have any specific questions.