Is it worth doing Mtech in ECE from the new IIT's like Jodhpur, Mandi or Bhubaneswar?

Yes, IIT Mandi offers a good curriculum, infrastructure, and placement for M.Tech programs, though they are newly associated. For ECE, IIT Mandi had only Communication and Signal Processing before but has started Power Electronics and Drives, and VLSI streams recently. 

Key Highlights:

• In the Signal processing stream, image processing, digital signal processing, speech processing, and random processes are covered. On the communication side, information theory, and analog-digital communication concepts are discussed.
• IIT Mandi has its own well-equipped communication lab, with national instrument kits 2920/ 2921, lab-view, and a lot more useful simulators and instruments. Image and speech processing requires algorithm development which is done using MATLAB. IIT Mandi has accommodation of its own High-Performance Cluster (HPC) for high-computing tasks.
• Students from M.Tech programs usually get internship opportunities in R&Ds mostly.
• From the perspective of placement, most internships are converted into per-placement offers.
• In an addition, IIT Mandi has excellent weather throughout the year, with amazing natural beauty.

So, it can be concluded that M.Tech ECE at IIT Mandi can be considered as a good option for students.