I agree with you about the bars. Most foreigner bars in China are grossly overpriced, the same with "Western" restaurants. I used to prefer to eat more Western style food in China, but finding a place that offers good value for money is difficult.
As for Chinese women who hang out in foreigner bars, yeah, look out! It could be more dangerous to have unprotected sex with them than even a local hooker!

I know one Chinese woman (27) who hangs out at ex-pat bars in Guangxi and Guangdong. She has slept with at least 100 foreign teachers and other ex-pats in the last four years. A 58 y/o friend of mine was having regular sex with her.

She is tall and pretty, but a golddigger. I was amazed my mate's STD test was negative! I know these guys don't use condoms, I never use them either, but to sleep with a woman YOU KNOW FOR SURE has had multiple partners is a bit insane! Can be lucky I guess.

I wouldn't touch her with a ten foot barge pole!

Ideally, we should all be using condoms, but in reality... Many people, that being girls not just men; don't like them and as for me personally, I find that locally made ones are a lot smaller, weaker than the British ones and I have had problems with breakages. Hence every time I go back home, I bring back a fairly large supply of British johnnies back to China!

Ultimately, that does mean that you have to be really careful. Hookers can actually be safer, they insist on condom use and take care not to get STDs, because once the word gets out that they have one, their main source of income is pretty much dead. Most slutty but otherwise normal Chinese girls don't tend to even know what an STD is.