The odd thing is if you asked me to do the accent now I would find it very difficult unless I was also playing that part, because I associate it so much with entering into the role and stepping into someone else's shoes.
I think we probably will end up in America because he would be giving up much more to come and live here. If you want to work in film, that's really where you have to be. But I'm not sure that being an ex-pat is very good for one's sense of self.