yes i took step 1. here's my experience.
http://www.valuemd.com/usmle-step-1-...-218-88-a.html
i got an 88/218.
the rotation i'm doing in connecticut does not allow students to rotate there unless they've passed step 1. the school can set up some of them, but i've also set up some myself. the NIH rotation was a tuff one to get. only 12 students will rotate per year in infectious diseases, and that's including all US med school students who are applying (who do get preference over us). only 1 student/month. there are around 20 elective rotations that they offer. the application process took 4 months, so you have to apply very early. in some ways, i like setting some rotations up on my own. it's not that big of a deal, and i can control exactly when i do rotations, and where.
just get that step 1 out of the way, and options are open to you.