Quality
I am not residing in China but with frequent visits to CP, Sh area and what I found is that the quality of pretty girls are not increasing even the economic downturn and factories close down. May be chics are heading back home instead. The prospect of finding new jobs in DG area is dim and girls can find decent job back home. So why stick around unless those want to make fast buck or those don't want to go back home because of personal reason. I know a girl who won't want to go back because they get used to the easy life in DG and won't want to live the tough life and cold temperature back home.
One thing I can predict is that with amount of factory closing down in DG and the new policy of stimulate internal growth within China, the samller cities will have more jobs available for the youth and they won't have to venture out to southern China in hope of finding decent living. NOt all girls want to get into sex scene unless the opportunity for fast and easy money are so enticing they could not resisst. The pooning business in DG area will not thrive any further and with the nearby factories reducing the related business will slow down as well. However, for the big city ; like Shanghai will be more MM available because more peasants still look forward to live in this hugh metropolitan city. From I have learnt, local Chinese still regards SH as the mecca for modernism and most desirable big city to live and to work. The attractiveness of big city of SH is like New York city to American people. They all want to own a place in the big apple or to visit because it sounds so chic.
So in the long run- like next 5 years, I don't see the DG will get more MM migrate there because of the slow down of growth and with the HK dollar is slipping thus affect the amount and frenquency of HKer's spend on this business will further eroding the existence of KTV etc...