Yep the plunger is the other amazing one. I would tier them as such:
Tier 1 - really useful
Tier 2 - mostly useful
Tier 3 - useless
I would swap the Magnetizer for the Swapper. I am useless with the Magnetizer but I have used the swapper many times to disrupt enemies who are going for a shot on goal.
Magnetizer is deadly, but it does take some time to get used to. It's low range is what put it into tier 2 for me. I used to think it was useless until I got better with it.
Swapper would be infinitely more useful and probably Tier 1 if it was instant. But 90% of the time you trigger it on a guy going for a shot/save and in the two seconds it takes to actually swap, he's already made it.
Though one time I did score an awesome goal with it -- swapped with a guy in the net as I was jumping at the ball, so his car ended up hitting the ball and I (obviously) just let it go in. Other than that though, I struggle to think of times it's had a real direct affect on play. A couple times moving guys out of the net and such, but that's about it.