I have to admit that I'm a bit at a disadvantage when it comes to verifying the authenticity of ethnic neighborhoods. After living in Japan for a while, I can say that Japantown in San Francisco is pretty good. But I've never been to China or India, so visiting Chinatown and Little India in Singapore doesn't give me anything other than the hope to get a feel for each country's culture.
That said, it was obvious that Chinatown was geared toward tourists. Hong Kong is westernized China, but it did have some realness to it... and Chinatown was not quite real. I'm not saying it's bad. But it's touristy.