IIT

Look, it totally depends on you. It depends on your field of interest and what you want to do. I personally feel there are two ways of choosing a college.
1. If you have decided your field and branch of study and you are determined in that than go for the branch irrespective of NIT, IIT or IIIT.
2. If you are unsure of the branch, then I would recommend, first research the course guidelines of the above-stated branches and outcomes of the same and then see which matches your interest best because 4 years is not a short period. Based on your decision, you have to study the particular branch for a long period. If you can see yourself studying that, then do apply. You have to be very careful while deciding this. Now, let's come to the studies, environment and other factors and most important to me. As I have seen, observed and talked to the peers in the IIT NIT and other colleges as well. Teaching is more or less same everywhere. In college, you have to study yourself and it is totally up to you, whether you limit yourself to college level studies or you study more advanced topic yourself, which you can do in every college. So, what all factors are left? Overall development: If you choose any old IIT, you will get tremendous opportunities to showcase yourself. IITs are the best in extracurricular. You name it and they have a club for each and every field be it related to technology, dance, debating, designing, journalism etc. The best platform to develop your personality, to try everything, to be around a good environment, to build good connections and networks is IIT. What I feel personally is, it is the best platform to discover yourself, to discover your interests and what not irrespective of branch. IIIT: They are the best in the field of IT, better than most of the IIT. And the graduation outcomes are awesome. But the extracurricular and the exposure cannot be compared to IIT. But then again, it totally depends upon you. Personally, if I would not have decided the branch then my preference level would be.
1. IIT
2. IIIT
3. NIT
4. DTU