well, a top20 MBA in US does make difference. remember that many companies only recruite certain ranked schools. (that does not necessary mean the opportunity is avaliable to everyone in top 20 programs)
otherwise, a chinese MBA is just as good as a US MBA
i really doubt the reliablity of the knowledge i get from an us mba. how many professor at the us study mainland china in depth? what the sources of the information they used for the research? cause, in fact, everything u read or learnd at this land, as called mainland, seems untrustable.
and, another problem is that the top 20 is not that easy to get an offer, doesn't it?