If i could go back and restudy and take step 1, I would have done more questions. Dont worry about wasting questions, there are tons of great questioins out there. Qbank is good, so is qbook, Appleton Lange, NMS, Many people that scored high did BSS, so there's no need to worry about running out of questions. At the same time, try to read and refresh as much as u cann too. You can learn tons from the explanations and it puts u in a good test taking frame of mind where u can pick out the right answer even if its written in spanish.
But i remember when i was taking the USMLE last year, not much of the test was in the books, u kind of had to figure it out right there. I will say that First Aid and these other HY notes can give u alot of free points, but to truly ace the test, u gotta master doing questions. Its just like the MCAT, people did a bunch of practice mcats and got a good score at the end.