I have used the universal remote for 2 month now and heres what I get:
Full controll of a mechanical target, like if you were it.
It is channelled, so don't get the robot too far from you. The time you have to controll it depends on your level. Or level of your engineering as most trinkets do. Maximum controll time is around 1 minute, enough to kill a robot of same level when you are in a group doing Gnomeregan and have a elete robot vs. elete robot fight. :D
Also for engineers it might be usefull do go Gnomeregan time to time because you might find Fused Wrings there, usefull for most trinkets.
It's not the coolest thing out there for engineers btw, here are a few:
Goblin Jumper Cables,
Gnomish Death Ray,
Gnomish Battle Chicken,
Parashute Cloack and the best 215 engineering out there:
Gnomish Harm Prevention Belt.
Have fun engineering :D