IIM Ahmedabad, Bangalore, Calcutta, and Lucknow are not suitable for the operations stream. If you are certain that this is the path you want to take, NITIE is the best option for you. The fact that the fees are less than half those of IIM C is an added bonus.
If you are unsure of which stream you want to pursue a career in or if you prefer a stream other than operations, IIM Calcutta is the best option.
Consider fees as an added benefit to NITIE. Do not consider it a deciding factor in your studies. Obtaining loans is simple; banks practically beg to lend to you. And once you graduate from college, you will be financially secure enough to cover your student loans.
There can be no comparison between NITIE Mumbai and IIM Calcutta. In any case, you can only go on to NITIE Mumbai in two varied situations,
Apart from these two, everything you require otherwise is considered better in IIM Calcutta.
But, either way, for General Management and various other opportunities, IIM Calcutta is undeniably better.