Other than to say in my three years here these are the first negative comments I've heard, I am not going to say anything further about Gallup.
What I do want to comment on are the negative comments the OP made with regards to Xian. Of course were all entitled to our own opinions. That being said, in my opinion, as someone whom has resided here for almost 3 years, the poster is completely off base with regards to Xi'an being a bad city. As far as being dirty? It is certainly no worse than any other your likely to encounter here in China.
The fact is Xi'an is an awesome city, full of rich tradition and history. One of the things I for one like best about Xi'an is the manner in which the government seems to work at hanging onto the traditional flavor of the city. Something Shanghai, Beijing, Chengdu, and some other cities certainly can't boast. IMO If you'd truly prefer to experience a more traditional China, Xi'an would be an outstanding choice.

Zhuhao!