i don't think it is all that important. i believe the people you know and the letters you get + audition rotations are more important (phone calls are key supposedly). your program is probably important insofar as it helps with the aforementioned. having a home program helps as they know you best.
i believe my senior medicine residents took step 3 after obtaining their medicine fellowships (in gi and allergy/immuno) and step 3 is by far more medicine heavy than pm+r heavy. most interns don't have a zillion hours to devote to step 3 anyway.
hey fozzy. i just took step 3 recently, passed it, and feel a hell of a lot better. our pgy4 applying to fellowships say it's not heavily looked at at all. the above poster is right. it's all about connections and doing rotations with them.
Just pass that damn COMLEX 3 so that you can start applying for state medical licenses. None of the fellowships cared how well I did on step 3. Take and pass the exam early so that you put full focus on PM&R. Who wants to study OB/Gyn during their PGY4 year when you need to get ready for the PM&R boards.
It all depends on the strength of your application (i.e. letters, connections, medical school/residency reputation). All the programs I applied for asked for it formally and some looked at it, particularly the anesthesia-based ones.
It probably wont make your application but if everything else is suspect it might break you.