Both IIM Calcutta and ISB Hyderabad are renowned universities in India, however, there are some significant variations between them in terms of their academic offerings, pedagogical approaches, and hiring practices. Some of the key variations between the two are as follows: 

1. Programmes: ISB Hyderabad provides a one-year Post Graduate Programme in Management (PGP), whereas IIM Calcutta offers a two-year full-time MBA program. ISB Hyderabad also provides a weekend management program and a part-time Executive MBA program.
2. IIM Calcutta uses a case-study-based teaching approach, whereas ISB Hyderabad combines classroom lectures, simulations, experiential learning, and case-study-based teaching.
3. Both institutions have knowledgeable and experienced faculty members, however, IIM Calcutta has a higher professor-to-student ratio.
4. Industry experience: Both institutions have excellent possibilities for students to connect with corporate executives and acquire real-world industry experience thanks to their strong industry collaborations.
5. Placements: Both institutions have a great placement history, however, ISB Hyderabad offers average wage packages that are larger than those at IIM Calcutta. Additionally, ISB Hyderabad has a stronger alumni network, which might be useful for locating employment possibilities.

I did not get what you want to know and compare exactly but assuming that you want to compare the MBA or the flagship program offered by IIM C and the PGPX course, as one is a college and the other is a course. 

The top Indian business school IIM C offers a two-year full-time MBA program. The program is for recent graduates or those with five years of work experience. The curriculum teaches management and business practices. While PGPX is a one-year full-time program for executives with at least five years of experience. The program trains experienced managers to lead their companies. The customizable curriculum is targeted at experienced executives.

In conclusion, the flagship program (MBA) of IIM C and PGPX offer management education, but their audiences, duration, and focus differ. PGPX is for experienced executives, while IIM C is for recent grads with little or no work experience.

IIM Kolkata and IIM Udaipur are esteemed Indian management schools that might lead to investment banking professions. The best investment banking option depends on personal preferences, professional ambitions, and networks.

However, program reputation, professor quality, alumni network strength, and school location may affect a choice between the two schools. Before choosing, examine both programs, talk to alumni and current students, and evaluate your aims and interests.

Regardless of education, investment banking success depends on hard effort, determination, networking skills, and the capacity to adapt to a fast-paced sector.

Irrespective of the B school you choose between FMS and IIM Calcutta, you will surely have a bright future with many job opportunities. Had I been in your place I would have gone for IIM Calcutta for the following obvious reasons:

• Infrastructure - IIM ABC are well known for state-of-the-art infrastructure and facilities which is lacking in the part of FMS. The quality of college life is a crucial determining factor for any B School. IIM Calcutta offers a holistic B School experience.
• Brand value: Sole of the most eminent personalities like Indra Nooyi and Ramachandra Guha, have graduated from IIM Calcutta improving its overall brand name. This branch-name comes into play while setting up your own business.
• Alumni network: IIM Calcutta gives access to the elaborate IIM Calcutta alumni base. 
• Entrepreneurship: Another major perk of IIM Calcutta is its IIMCIP or innovation park to incubate promising startups. It has produced alumni like Ajit Balakrishnan (founder of Rediff.com) who have started and led successful companies.

FMS too has an elaborate list of successful alumni but IIM Calcutta is clearly a winner here.

For those who claim FMS provides better ROI, I don’t think a 20 Lakh loan might be an obstacle to your entrepreneurial plans. Most education loans have repayment periods of 15+ years and banks waive off interest rates and collateral requirements for IIM students. 

It all depends on what you want out of life. If you have more than three years of experience, you should apply to ISB Hyderabad or IIM Calcutta. Furthermore, ISB offers a challenging 8 semester in 12 months program that prepares you to handle any type of workload after that.

Though IIM Calcutta is excellent for finance professionals. If that's the situation, you can go for it. You should not compare the one-year programs at IIM Calcutta and ISB Hyderabad. If you are, ISB is far superior.

As an Indian in Europe, your employment prospects are limited because all students in France anticipate a period of transition between education and work. Alternatively, if you enjoy studying so much, you could pursue a career in academia, where Europe is the best option in the world, and you will begin publishing while completing your Master's degree.

The placements at IIMC are extremely uneven. In Calcutta, you will be stuck in a back office job for giving them a good grade and will regret it for the rest of your life.

IIMB is a well-rounded Finance option with a strong emphasis on placements. If you want to make money from any IIM, consulting placements are plentiful.

Overall, if you can afford to wait a couple of years for OIIT to click, nothing beats a trip to Paris and a one-year Master's at EDHEC for an undergraduate experience. If you have EDHEC, Wall Street will assume you have enough.