Which is better NSIT or VIT Vellore?

I will recommend you choose NSUT over VIT any day. Here are some strong points that support my recommendation

• NSUT has a better crowd quality than VIT. They have cleared one of the toughest engineering exams, JEE, and are also good at coding or Electronics.
• NSUT  has a few exceptional professors like Dr Harish Parthsarthy, who are experts in their respective fields and also have a passion for teaching. 
• VIT is a private institute and receives more funding for research work. But the research culture at NSUT is also good. It has amazing research facilities like Texas Instruments Centre for Embedded Product Design.
• NSUT placement scenario is top-notch and has a record of several students getting placed in Google. Some other major recruiters are TI, Adobe, Amazon, Samsung, Google, ARM, Airtel, CISCO, and various others. 

So, if you ever have the chance to choose between NSUT and VIT, always choose NSUT without any second thoughts.