IMG from India, top 3 medical school, but never a diligent student. Graduated 2014. Gave Step 1 end-October.
I took about 5 months to prep, but was dilly-dallying early on (had about 5 different research projects on at the time) so I only took things seriously from mid-September. Did Kaplan early on, found them very useful to orient myself to the conceptual slant of Step 1, especially as I had never considered taking the USMLE when I was in medical school itself (our curriculum is geared very differently). Also used Goljan RR, FA2013 and UW (73% one pass, timed random). NBMEs went up by about 10 points each time I took them, from 211 in June (prior to starting) to 235 in August, 243 sometime in between and finally 251 on form 15, ten days out.
My exam felt like a mix of NBME and UW, but lots of weird ethics and biostats questions (what I'm weakest at; about 20% of my test)
I ended up with ~255. My advice is to make sure you know FA really well. Although I know that I must have missed loads of questions on ethics and weird out-of-the-world minutiae, I was pretty sure that I had not messed up anything that I had already read from FA or Goljan. Be ruthless when dealing with questions to which you know the answers; avoid human error. This is particularly important because the USMLE tests stamina as much as it does knowledge and common sense.
Good luck to the rest of you! Illegitimi non carborundum!