Hello

Both the colleges have its own pros and cons.

The ratio of number of companies visiting campus to nunber of students is more in IIIT Allahabad . In simpler words more opportunity in IIIT Allahabad.

As per ranking IIIT Allahabad is at better position than NIT Durgapur. Even fests are better than that of NIT Durgapur.

In terms of branch.... CSE and IT seems same but both are different a lot CSE deals with mathematics , programming , algorithms, while IT is much more safer side of Computer science it includes Computer fundamentals not in depth study and management/ services skills.

I think you opt for CSE in Durgapur because A computer science graduate can also do a job of IT professional. At NIT Durgapur you'll enjoy all the name and fame of college. Fees is also less and you'll get good job opportunity.