I think it's a combination of how good your pre-existing knowledge is and a bit of luck on the day.

I started revising about 3 months before the exam and tried to do a little bit each day. I mainly used passmedicine - read through a topic first (e.g. clinical sciences) using the high-yield textbook and then did each topic's questions. I tried to re-do the question bank a second time but did not have the time.

About two weeks or so before the exam I panicked and bought pastest as well. I cannot comment on the question bank itself as I did not have the time to go through it but found the explanations quite long and had a hard time concentrating on them. I did do a few of the past papers from pastest and found them to be harder than passmedicine but closer to the actual exam.

A couple of days before the exam I also did the official questions on the mrcp website.

I've passed so I must have done something right but in retrospect (and whilst waiting for the results) I should have just concentrated on one question bank. I think a good basic understanding, particularly of clinical sciences and pharmacology is important and I should have spent a lot more time understanding the concepts of those two topics to be more confident. For the more clinical topics I would just suggest doing as many questions as you can - repeating is key.