Having a MIDA user in your fireteam can be very usefull if you ask me. The stagger perk is pretty amazing and gives you that extra second to take out those dangerous targets. (rushing melee knights or ogres for example) The increased aggility could also be usefull if you are the relic/sword holder in the raids. I must admit I use my exotic spot for a Gjallarhorn or an Icebreaker much more often but there are situations the MIDA is the (multi)tool for the job. :)