It's hard to decide. In the Hall fight it was clear Butler was the better boxer, but he looked tiny and lacked power. With McDonnell he's big at the weight and has a great engine so for me I'd say Jamie wins. But if it did happen i'd be cheering for Paul.
Jamie wins this. As skilled and effective he is as a super-flyweight he's just that bit too small for bantam and McDonnell is a big boy for the weight and proved against Ceja he can deal with good front foot fighters. In a few years when Butler has filled out a bit this is a different story.
Jamie wins all day long. Butler was extremely lucky to get the nod versus Hall and would be bullied by Jamie.
As much as I like Butler and he has bags of talent, styles make fights and I'd go with Mcdonnell + I think Mcdonnell would have to much size for him at this moment in time.