I run 4 accounts selling basically the same items . I don't have a store so I just use different account to categorize.
I moved three of my account to .com because I have always sold in USD. I kept 1 account on .ca and have been completing drafts as they expire.
I have been have a very decent week with the three account that are on .com. The account on .ca is dead. Barely any watchers. I did actually sell 1 though , but that one was still listed in USD.
I am convinced that when using the migration tool and it changes currency to Canadian, that higher Canadian dollar number listed plays a trick on buyers minds. Yes its in Canadian, but its the number buyers see.
I have given .ca a shot , but its time. I have to move this account to .com as well.