After using USMLEWORLD's surgery questions, I realized that it was too ortho heavy which is not a good representation of the real exam whatsoever. There were a few questions that were helpful for the shelf but you have to realize that the Surgery shelf is not like most other shelves. I was told that it's a medicine shelf which I don't agree with either. After taking it, I think it was a mixed bag of just about everything - Medicine, Peds, Ob/Gyn, Psych (yes, I had a question about how I would manage a case ethically). Common sense also went a long way on this exam. It helped that surgery was my 2nd to last rotation so I wasn't as baffled as others might have been but it was still a tough exam.
sorry for the side tracking regarding surgery. As for other rotations, I haven't used USMLEWORLD however know of quite a few other students who have and love it. For Ob/Gyn, the UWISE questions are more representative of the actual exam IMO. At the end of the day, UW is probably a better question bank for any rotation compared to books like pre-test and what not.