It's been a while since i took my ppl exams, but I remember the confuser questions being very similar, although not exactly the same as the real exam.
In subjects like law and HPL, there are only so many things they can ask so the confuser will be close to the real exam.
In subjects like Nav, you need to be able to calculate things, so the confuser will be a good learning aid, but will not give you the answers for the real thing.
Someone at my flying school just took a met exam which has just been released, and he said the confuser was no help at all, and he hadn't seen anything like the questions before.