Even if his suit can't be turned against him, what the hell does Iron Man have that can do anything to Megneto at all? Unless he decides to bust out the Infinity Gem the he has I can't think of anything that he can do that can't be countered by Magneto, and there are quite a few of his tricks that can be turned completely against him.
I can only imagine the crap they are going to have to pull in order to actually let Stark win.
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SuperNiceDog had a super nice bracket too.