Most people, certainly on here, thought that Maddison was nowhere near as good as Jack when he made his £25m move, but he made a real impact in the PL last season. He has set quite a decent bar for Jack to match up to, that is the challenge for him if he has England aspirations.
Mount looks a good player too and is in the same boat as Jack regarding this being their chance to make a mark, he has gotten the headlines so far but over the course of the season I would hope Jack will have pulled well ahead of him.
It's all in his own hands.