This is a common dilemma faced by many who are applying for MSc. It requires a great research-oriented approach and thus the choice of the Institute should depend on the research work and projects offered by that institute. One needs a wide range of choices of courses so that you can select the one that matches your area of interest.

Before researching campus life, look up the faculty profiles available on the official website of the institutes. Once you come across a profile with the kind of research work you are looking for and want to work on, then choose that particular Institute.

My friend chose IIT Madras because she found diversity in the fields people worked in there. You can find people working in almost every field from Experimental Condensed Matter, Theoretical Condensed Matter, Nanotechnology, General relativity, and cosmology to String theory, Quantum computation, and chaos, High energy - particle physics, Theoretical and Experimental Optics, and Mathematical aspects.

IIT Madras maintains the right balance between Experimental and Theoretical Physics which is sometimes not possible at other IITs. Despite this many flocks to IIT Kharagpur mainly because of herd mentality. In reality, IIT Madras has a lot to offer provided you are committed to doing your part of your efforts.