But people know it's not genuine, especially since you know the EX edition size is 1,250 and the regular edition size is 2,500. It's not a true matched set.
I get what you are saying but if you don't care about the Ex head and someone else does then I can see selling it.
If you have a reg statue with the EX head sure you are not going to get top price for it as you would a full EX statue but if it becomes a hard to find piece I think you would be surprised to find that people would be willing to shell out a good sum of money to have a Reg edition with an Ex head.
It's like the Statues that sell high without the original box. They may not sell for as much as those with the box but they still sell well.