Need Advice on 4th year electives

Hey guys-

Basically, I've got a 4th year elective at Sloan Kettering in the Medical Hem/Onc department set up for October; however I'm also awaiting word on Hem/Onc for the same month at the Harvard Hospitals (I applied for at all 4)

Now here's my dilemma: As far as my interests go- I'm very interested in Hem/Onc with eventual fellowship in mind and am pretty excited about being at MSKCC for a month in that environment

But as far as actual Residency app stuff goes I'm definitely going to be applying out in Boston (with MGH,BW = reaches, BID = high on my list, potentially a reach) and since MSK doesn't actually have residency positions at their institution I think overall doing an away at BID for example might be more beneficial

As far as goals of the rotation go I'm hoping to get a letter either way (It's pushing it I know) and again HMS hospitals are all on my list for IM residency as is Cornell for that matter

Anyway, any input would be greatly appreciated.. thanks!