IIITMG was established in 1997, 8 years before IIITDMJ came into existence so it is a decade older, so you can understand that it has better infrastructure, reputation, placements, etc. I agree on all points but...there is a flip side to the coin let's see that...

Let's talk about placements, IIITMG have way better placement record than IIITDMJ no doubts but we all are comparing placements of undergraduates with those of graduates i.e. person holding only 1 degree of B.Tech. (IIITDMJ) vs people holding dual degrees, B.Tech + M.Tech/M.B.A. (IIITMG) and MBA is a hotshot, as of now in our country. If there were 4-year programmes in IIITMG then it would have been fair to compare both the institutes in terms of placement.

Now, let me tell you why you should think twice before enrolling in a dual degree course…

First Case: You want a job as soon as you are out of college and don't have any intention of going for further studies.

If you are enrolled in a dual degree programme, then this freedom is taken away from you not only you will start earning after 1 more year as compared to your friends but also you will need to complete the second degree before you can start a job. If you are able to get a whooping package after that 1 additional year then it is worth investing, otherwise it’s just waste of time.

Second Case: You want to go for further studies.

In this case being in a dual degree programme may seem like a blessing as you are saving 1 year, but in the hindsight, you are limiting your future scope as you have to complete the Master's degree from the same college. You are sacrificing a chance to move to a better institution (IIT maybe) and also you are sacrificing your chance for M.S. from a foreign university. Still, want to save that 1 year? Now, you got a better starting package then your friend with only B.Tech. degree but he did his M.Tech. from IIT-B…who won?

Third Case: You want to pursue M.B.A. right after graduation.

Congrats! You are saving your 1 year and the pain of preparing for CAT. But (yeah you understood) you are giving up your chance of a shot at IIM or at GMAT(MBA from abroad). Similar case as above.

It was my job to tell you about the consequences of dual degree which sadly no one else mentioned here but still, it is your choice to make. IIITMG is a great institute no doubt even better than IIITDMJ and if you join it you may get a better placement but that 1 year makes the difference. Just introspect, discuss with your parents, tell them pros and cons and together take a calm decision and then stick with it firmly.

Hope this helps. All the very best for your future!