Disclaimer: I am an IMG who studied slowly throughout school but took the exam soon after graduation. If you are a US student this will probably not apply (prep is usually very different). Also, I am still waiting for my score (next week prob.)
I did Kaplan Qbank once, starting about three months before my exam. As I reviewed each block, I added most of the incorrect questions, correct questions that I had guessed or just concepts I really wanted to reinforce, to the Kaplan "My Questions" feature. The idea was to only go over THAT in the end. When I finished I had about 700-800 questions in there (that's like 30% of the entire bank) and I didn't have to go over them all, only maybe like half. Most other people do recommend going over the banks at least twice, so if you have the time go for it. I felt that doing the ENTIRE bank twice would have been a waste of time, so I planned to go over those "My Questions". Kaplan makes it really hard anyway to go over it twice, I think it's really hard to get their customer service to reset it (even the "My Questions" feature was hard to use - it's hard removing questions from the list once they're in so when you do questions from there, you get repeated questions frequently - the whole "my questions" is a crappily implemented feature but it kinda sorta works)
Most people say Kaplan's Qbank is overtly detailed and is unnecessarily hard. The general opinion is that UW is more similar to the exam in terms of difficulty and content. Kaplan DOES have some weird questions on details that I had never heard of before. I cannot personally compare to UW because the UW I used is an old 2007 version leaked on the internet.
1. I got Kaplan because it was $200 for a year, I didn't reallyl have any other reasons to choose that over UW. Ended up enjoying it and I don't regret having used that instead of UW at the time
2. Kaplan may be nitpicky, but because I didn't have issues with the general concepts, only very specific details (chromosomes/genes/specific mutations, weird drugs, weird uncommon syndromes) I think this helped me prepare for the worst
3. I used the 2007 UW which is admittedly outdated, and also seemed WAY too easy (very few nitpicky questions). But UW questions are the closest to the real exam in terms of wording and the types of answer choices.
4. I only went through Kaplan's Qbank once but a year before that I had done most of usmleRX (terrible at the time) and many question books, so technicallly I didn't JUST use Qbank's 2400-2500 questions
5. I don't think I ever felt that I _didn't_ have a grasp of concepts (only a few specific hard concepts) but that was because as I studied each subject/system I did questions off books (Pre-Test, FA Q&A, Kaplan Qbook, BRS has a few questions, also Robbins question book). I used my PAID subscription to questions as more of a final review, and to iron out details, rather than to learn the material firsthand (this is what people call learning tool vs. testing)
Hope this helps
