How good is IT at IIIT-Allahabad compared to CSE at BITS, Pilani and IIIT-H?

The answer depends on your preference, CSE and IT are completely different courses. If IT is your choice, then IIIT Allahabad is the best option for you. But if you want to go to BITS Pilani or IIIT Hyderabad you could research more about the college and interact with people who have studied there. So, you will get a good idea about the institutions.

Winning Institute:

Choosing among the three brand names of engineering is stringy, but the IT program at IIIT Allahabad is top-notch.

CSE v/s IT:

• CSE and IT are two different courses which usually confuse people.
• CSE deals with the science that facilitates the application of computing technology to real-life processes, i.e., it covers hardware and software. In short, CSE deals with the scientific study of computers and their research applications.
• IT deals with just the application of computing technology to real life, i.e., it is a more software-oriented course. In short, IT deals with the industrial application of computer science.

If college isn’t the priority, you can choose to focus on the subjects of these courses. 

IIITA exists in the shadow. It needs a lot of popularization, but it is best for IT. IIITH is best among IIITH and BITS Pilani for CSE Branch.