See, if you want a secured future and want to get into a high paying job straight out of college, especially for M.Tech, then I would suggest you to go with BITS Pilani Pilani campus.

BITS Pilani has a much higher recognition and alumni base as compared to all the 3rd Gen IITs that you have mentioned. And the developments that have happened in these 3rd Gen IITs have only been on the front of B.Tech.

If you would have asked this question for BTech, then I would have recommended you to take IIT Bhilai over any other college, but if you want to go for M.Tech, then BITS Pilani is the logical choice. All the best!