A lot of it depends on where you are at prior to really starting to study. If you do really well on the 1st comp, i.e. 80+, then you can really focus more on the areas you are weak in. I would say that involves using First Aid and Usmleworld questions and maybe using a more in depth resource such as Kaplan for the areas you need to study more in depth. If you need a more comprehensive review for step after the comp, then you probably need to focus more on using something like Kaplan or taking Falcon. What you don't want to do is to have too many resources that you are constantly shuffling multiple books for the same subject. If you are doing a more comprehensive review, I would only use First Aid supplement to see if Kaplan is missing something high yield. I will also add that if you use anything other than Rapid Review Path for the step, you are not doing yourself a favor at all. Goljan's book is the most comprehensive book out there for path and can be used even after finishing step 1 for later exams. I will also recommend not focusing too much on treatment for step 1 because it is more focused on understanding the path, phys, etc. The pharm questions are focused on mechanism for the most part. If there is a clear drug of choice for a certain bug, then I would know those, but don't try to learn everything a particular drug can be used for. First Aid is probably a pretty good source for pharm because it does focus more on high yield.