I started studying for the USMLE Step 1 back in January while doing my last semester of Basic sciences. It was hard to balance board prep with classwork, so I really didn't get much done during those four months. My real prep started at the end of May. I had a good 7 weeks of pure Step 1 preparation. Here is my performance on the practice tests I took:
Free 150: 80% (6 weeks out)
UWSA-1: 247 (4 weeks out)
UWSA-2: 265 (2 days out)
Cumulative UW average: 82% (first few blocks were in the low 70's, last few blocks were in the high 80's)
I didn't take any NBME's. Why? Because after paying more than $850 to register for the USMLE (as an IMG), I didn't want to spend another penny that would go to the NBME. It should not cost that much to administer an exam! With all the money they suck out of us, you'd think they'd take the time to update the software they use for the NBME practice forms! They don't! They use outdated software that was used years ago and is different from the current FRED 2.0 software they use to adminster the USMLE. You also have to pay extra if you want to find out your answers on the NBME practice exams (If I remember correctly, an NBME is about $40 without the answers, and $60 with the answers).
I went with the UWSAs because when you buy USMLE World, you can get the package that gives you access to the Qbank, UWSA1, and UWSA2 for $130 (1 month subscription). If you consider that the subscription to the qbank by itself is $99, that's like $15 for each UWSA, including answers, explanations, and software that is almost exactly the same as the FRED 2.0 software. Anyways, that was my rant for the day.
According to my performance on UW and UWSAs, my predicted score should fall in the 250's. Crossing my fingers for this!