Since the update where Kabam fixed an issue where you could continuously throw a heavy and keep the unstoppable up, magneto is now even better.
In typical Kabam fashion, they now made it so that magneto can keep his unstoppable up 100% of the time by holding heavy and canceling it using a sp1 or sp3. Only way to drop the unstoppable is to re heavy.
Video below!
https://youtu.be/QDHxO52YQhs