I do question where he'd fit on our defense. My biggest concern is with his speed getting off the line. Not sure if he's hurt or they scheme it that way on their defense but it's so blatant. I think if that's a non-factor he's a pretty talented guy.
I think he's been playing through injury some this year. What he lacks in getting off the line he makes up with shedding blocks and getting to the ball.
As far as the OP...besides Marks, what talented pass rusher are you worried about taking off the field when you move Williams around? If he's an all around player like Watt, who doesn't want that?