I know this is wrong for me to say, that as much I respect Ian Mckellen I don't think he portrayed Magneto (then again I'm wrong) character-wise when I look at Magneto, I think of him more scary, intimidating for example.
This guy, Charles Dance AKA Tywin Lannister from Game of Thrones.
Don't know why but after seeing his acting on the show how he command the entire scene he's in. I believe comes of more Magneto-ish. Just saying, also he look like an older version of Michael Fassbender.
Speaking of which, he is doing a great job portraying a villain as always,he just doesn't look like Ian Mckellan(and I know looks don't matter) but when I look at a young version of him. I think of...
He looks like him,sounds like him, he could be him
But these just my opinions.
Tell me what you think?