Both AIIMS and NIMHANS have been excellent institutes for neurosurgery. Both the institutes have their unique strengths and weaknesses. It’s better to weigh the pros and cons before coming to a final decision.
AIIMS Delhi
NIMHANS
Both AIIMS Delhi and NIMHANS are equally good in terms of the amount of work, patient management protocol, and infrastructure. The only issue at AIIMS Delhi is the increasing staff as a result of which the surgical work gets divided and residents get less work. NIMHANS on the other hand has a lesser faculty count which does not necessarily mean more work.
Ultimately, it’s your performance that determines your success and not your institute. Institute just lays down the stepping stones for your future.