Commercial Pilots will tell you that a high percentage of the content of the ATPL course is not used when you fly commercially, so does it really matter how you get through the exams?
I'm not sure what the answer is, but I actually found studying the subjects very interesting and that encouraged me to read it carefully and actually understand it. If you don't have that motivation then perhaps you're doing the wrong thing!
The fact of the matter is that the Question Bank undoubtedly makes it easier to get a high grade, but it isn't a substitute for proper studying. I used a mixture of studying the Bristol GS course materials and then spending two weeks going through the QB over and over again. I met plenty of people who would have failed the exams without the QB because they didn't want to read the whole course. That kind of attitude and 'mis-education' scares me!
I can say that I didn't use the QB for Module 1 but did use it for Module 2. My average grade for Module 2 was 10% higher than for Module 1. I attibute it to the QB.