I have done better than average on both COMLEX and USMLE Steps/Levels 1 & 2, and I agree with Tom here on this one.
There were soooo many questions on USMLE Step 1 that I had to reach back into what I had learned during the first two years. So, study hard now in the classes that you are taking, but I wouldn't get Qbank yet, it would be waste of money. Learn what you need to on each system or however your curriculum is set up. If you learn as much as you can while you are taking your pre-clinical/basic science courses, you'll be prepared for Step 1.
My advice that I have been giving to 2nd years/3rd years at my school is to try to finish First Aid(and/or StepUp) about a month or so before your boards, then just do questions. (I did NMS, A&L's, and some Qbank). I think you are wasting your time if you are reading on topics within a month of the boards. You are going to be burnt out, sick of it all, and questions help focus your attention when you are exhausted. If you want to look stuff up that you missed that's different, but don't just sit down and read stuff. DO QUESTIONS!
If you really want to be successful, I would start out doing questions, etc. on your weakest subjects so that you don't leave them until the end. I did that and I really think it helped, especially with Step 2, and I remember even with Step 1.
For Step 1, our school gave us the practice USMLE that can be ordered and administered by the school on a Saturday...my worst subject was Renal so i studied that hard before Step 1, and wouldn't you know it...it was my best subject on the real deal, and I remember there was a lot of renal on that test.
Same thing for Step 2...I started out with Peds(esp. Immuno Dz's), OB/Gyn, and Psych b/c I knew they were my weakness and it really helped b/c my Peds turned out okay and so was Ob/Gyn. Okay...Psych was still my lowest, but who cares, those questions are as nutty as the patients.
And what was I off the charts in again on Step 2????
"Renal, Urinary & Male Reproductive Systems."
Boy are those Kidneys important..... 😀
Good luck! And don't you dare sign up for Qbank yet!