IIIT Allahabad is the institute of national importance, whereas Thapar Institute of Engineering & Technology is a deemed university in Punjab. The best institute among the two for pursuing engineering is IIIT Allahabad. It is far better than Thapar. Here is a brief overview of the institutes.

• The tag of IIIT is an advantage. IIIT Allahabad is not less than old IITs as it is one among the Tier-1 colleges for engineering.
• The quality of research and reputation it has in the industry makes it a lucrative choice.
• IIIT Allahabad offers only two specializations, IT and ECE. It diverts the complete focus on these two branches.
• The faculty of the institute is skilled in teaching and has vast experience in the industry. They use the industry-specific teaching approach and prepare the students to take up real-world challenges.
• The coding culture of the institute is renowned in the country. It has given birth to many excellent programmers in the world. Every year, a team goes to compete at the international finals in ACM ICPC. Heard of ‘Humblefool’? Till date, he is considered the best programmer from India and he belongs to IIIT Allahabad.

Overall, the above points conclude that IIIT Allahabad is not only the brand, but it also gives the best return on investment.

The change of branch is achievable while the change of campus is not. The following example may clear your idea about the branch change between the institute. 

Branch Change:

As of now, IIIT Lucknow only has two branches. If you are enrolled in ECE in IIIT Allahabad, then you can try changing it to other branches in IIIT Allahabad.

That means, if you are in IIIT Lucknow, then changing the branch to anything offered in IIIT Allahabad is not possible.

IIIT Lucknow:

• Yet, if you consider the facilities that you can avail at IIIT Lucknow, then the choice can be worth it. The students of IIIT Lucknow can be on the list same as IIIT Allahabad, or sometimes even higher.
• The campus may take some time to be developed properly. Apart from that, it certainly is a good choice, provided the circumstances and the support received from the seniors.
• IIIT Lucknow is one of the major 20 IIIT institutes in India, that basically was established under public-private partnership mode.
• Graduates from this institute get their placement in top-notch companies such as Google, Amazon, Microsoft, Collegedunia, LinkedIn, Nykaa, Samsung, Paytm, etc.

Also, students from either of the two institutes, namely, IIITL or IIITA are not treated any differently.

According to my alumni connections from both the colleges, IIIT-Allahabad should be your priority for any degree in information technology. There should be no doubt if you are comparing with IIITM Gwalior. IIIT-Allahabad has an edge over IIITM Gwalior because of these two major reasons:

• This institute has produced a well-known alumni network around the globe that too in a short span of time. So, choosing such an institute with a good academic, industrial and alumni record will definitely prove to be much helpful for you.
• Also, IIIT-A has a better placement record than IIITM Gwalior which is often seen as a priority by many of you.

Both are very good institutes but definitely, the IIIT Allahabad is better. However, in case your pool of interest is information systems management, then you can blindly go for IIITM Gwalior, as they provide integrated degrees in IT and Management.

Firstly, you should know that there is no difference in the facilities and reputation of the colleges, Although BITS ranks better as an engineering school. BITS Pilani ranks #30 on NIRF's Engineering rank list and IIIT Allahabad ranks #103 on the same. But you should focus on your monetary capacity in consonance with your future plans before applying. 

My cousin studied at IIIT A and the following points are based on his experience:

• IIIT A is an excellent place to study coding. The classes are good although the syllabus has to be maneuvered because it's tough. You can manage it through attention in the classroom.
• Attendance is an important part of the academic process here because IIIT A has a 75% mandatory attendance rule.
• Without a doubt, BITS has a higher fee range as compared to IIIT A, about 7 LPA for a 4-year program.

Here's a table comparing both institutes:

Lastly, if you love the mechanical stream and are truly motivated to study Maths and Physics then you must go for it. Mechanical is a vast field as well because you'd learn everything related to mechanical processes and even production scheduling. So clearly check your interests and goals before deciding.

When choosing between several institutes, there are various things that you need to factor in before arriving at any possible conclusion. The first thing you need to decide is what matters to you most: branch or institute. If you have a specific branch in mind, you can definitely choose either of these two institutes. You can rest assured about placement as both of these two offer good placement to the students. 

Whereas, if you are more inclined towards choosing a better institute, irrespective of the branch, you can choose MNNIT. 

However, according to various reviews, the most preferred order for these choices among students are as follows.

• CSE MNNIT
• IT MNNIT
• IT IIIT-A
• CSE/IT MNIT 

Further, CSE and IT offer almost the same opportunities, and points 2 and 3 are interchangeable at times.