What is it like to do an MS in IIT, Mandi?

To be very honest, doing MS from IIT Mandi is not a great decision. It completely depends on the branch that you choose. Suppose you choose Computer Science (Image Processing and Communication), then you may get better results with respect to placements. If you choose to pursue MS in Electrical: Control, Power Drives, Sensors, etc., then the chances of placement are very minimal. For the other branches like Thermal, Design, and Material, etc., the only option you will have is going for a doctorate. 

Although, if you have set your mind that you will go for a doctorate program after MS, then IIT Mandi is a good option because the tag of IIT will definitely help you in the future. But in case you are hopeful of getting placed after completing MS from IIT Mandi, then you are at the wrong place. Choosing one of the old NITs will help you more.