Which one is better, NIT or NSIT?

Both NITs and NSUT have their own plus and minus points. Let us look at a few plus points of NSUT Delhi-

1. Placements - It has better placements than all the NITs, DTU, and even a few IITs.
2. Location - It has a locational advantage as it is in Delhi. Also, it is located near the metro station, so you can travel across Delhi quite easily.
3. Campus - The campus is good. The academic, administrative, and other departments are located near each other. There is a large playground, sports facilities, and a running track. Parts of the campus are covered in a lush green forest. 
4. Faculty - The faculty consists of two kinds of teachers. First are those who teach really well, are regular, and give good assignments and valuable learnings. They are supportive and encourage the students to indulge in project work.

The second category consists of those who are there just for the sake of it.

But even NITs have a similar situation in this regard.

In terms of project opportunities, lab facilities, technical fests, and technical societies, the NITs are a better choice. 

Depending on your priorities, you can choose between the two. NSUT Delhi is a great choice if you wish to study over there.