If you have a billion chines people living at the same living standart as you are, there just won't be enough ressources for all of us. It would lead to war eventually in my eyes.
Even worse if they have all the technology then we are useless for them. Right now it is a biliteral relationship. They get all of our technology, we get all the cheap labour. Take on away we are screwed. Americas and especially Germanys driving power behind our export is our knowledge. If China catches up with us we won't have anything to sell anymore on the market. What do you think will happen then?
Well you can forget about the lifestyle you have now