My step one score was right about the national average for matching in surgery, and I wanted to do a little better to hopefully secure a few more interviews.
I finished my third year on my medicine clerkship, then, at my school we had a two week break. So, I basically studied my *** off on during medicine, and spent the two week break doing peds, ob, and the rest that I hadn't seen in a while. I also took it early because I did my surgery sub-i in july, then 3 visiting rotations at places across the country and I wanted to get it out of the way before all that happened.
I improved my score by more than 20 points, and wound up getting a bunch of interviews I didn't think I would. Even though I thought the test itself was much harder and more ambiguous than step 1. And, in at least 75% of the places I went, at some point during the day, an interviewer would comment on how much score improved from step 1 to 2. I wound up matching at my number 1, and I doubt I'd have been ranked very highly due to my average step 1.
I think, like others have said, step 2 can really help you, IF you improve on it, but it's hard for a lot of people to not want to take a good long break from big tests after the stress of third year. I took it early, then scheduled a bunch of easy rotations this semester, and finished med school at the end of March.
I'm happy I took it early, but I'd probably be singing a different tune if I hadn't put in the work to improve my score. Good luck.