Both are the decent Institutes. Visva-Bharati was declared to be a Central University and "An Institution of National Importance" by an Act of Parliament. It was granted the status of a unitary, teaching and residential university. You can check the other detail with the given below link.

http://www.visvabharati.ac.in/Courses.html

The academic programmes at NISER are deemed to be conducted through the Institute of Physics, Bhubaneswar, which is affiliated to Homi Bhabha National Institute. NISER insists on student evaluation of each course and the concerned instructor at the end of each semester. This is an important part of a self-correcting process. Students are encouraged to think in terms of making a qualitative difference in their learning outcomes rather than merely attend classes. You can check the other detail about it with the given below link.

http://www.niser.ac.in/content/education-niser

Good Luck!