I've never been inside a textile factory, but I've been inside Chinese factories that make automotive parts. I've never seen children working there, but a lot of young adults. These are not slave labor camps, the people who work there choose to work there, although the working conditions are not what a lot of us would tolerate. I won't refute that child labor and forced labor exist, I've just never seen those conditions personally, and wouldn't automatically assume that because a company outsources to China they use these methods. One thing I know is that you probably buy products from China. Your German car is filled with parts made in China, most of them shipping to Europe for final assembly. If you have an iPhone, it's made by foxconn,
http://www.nytimes.com/2010/06/20/we...20barboza.html. If it's the case that textile factories have particularly worse conditions than other types of factories in China, then the self-righteous move of not buying clothing made there while buying other products made there might be the correct one.
As to the middle class in China, I see more wealthy middle and upper middle class people every day, and these people seem to be buying cars and western brand clothing. The difference from five years ago is astounding. These are just my observations, though. If there are statistics that dispute them, I couldn't argue with them.