I am a junior premed college student and have been offered a summer research opportunity at the NIH and one at my target medical school. The topic of the research is very similar at both places, so I would be doing similar things at both places that are of interest to me. Would it be better to accept the opportunity at my target medical school (which is my in-state medical school) to gain networking opportunities there that may increase my chances of being admitted there for med school or should I accept the NIH position which is a prestigious place with tons of interesting research?
Either will enhance your application; however, the NIH summer research experience will open more doors for you, especially since you --like all pre-meds–will need to apply broadly to have the best chance for a med school acceptance.
IIRC, the summer program at NIH holds weekly seminars on how to apply to medical school w/guest speakers from several medical schools. There may be (or at least I think there used to be) the opportunity to take a MCAT prep class on the NIH campus too. (Not included as part of the summer program, but available for those who are interested.)
The NIH program will also give you boost in finding research assistant jobs post-graduation if you plan to take gap years or if you decide you want more research experience to enhance your research CV for a MD/PhD or a research intensive medical school.
The biggest issue with the NIH summer program is finding inexpensive housing near Bethesda. (But, IIRC, you can rent dorm rooms at American for the summer for a pretty reasonable cost.)